Skip to main content

OpenAIAI Model API

OpenAI API

OpenAI's platform for teams building AI features and agents on GPT models. The Responses API supports function calling and remote MCP servers. Prompt caching, Batch, and Flex reduce usage costs, and the Agents SDK runs agents.

The 30-Second Take

Pick the OpenAI API if GPT models belong inside your own software and you want each new model on release day.

OpenAI sells it per token, and Azure and Amazon Bedrock resell it. DoorDash and Grab run it beside Azure OpenAI behind their own gateways.

Best fit
Product and platform teams building AI features and agents on OpenAI models in their own software.
Main constraint
Usage tiers cap monthly usage and throughput until spend history builds, so launch capacity depends on your tier.
First move
Run your evaluation set on GPT-6.1 Sol and GPT-6 Luna with caching on, under a project hard spend limit.

Why

Watch the migrations: WebPlanning's voice agent fell from 98% to about 25% successful commands on gpt-realtime-2.1. Qualify every model change on your own tests and keep a second route, such as Azure OpenAI, ready.

Practitioner sentiment, teams and leaders+3 Mixed

62 practitioners, 154 sources reviewed, Updated Oct 30, 2026How this is measured

Read the GILD Review
Save a product your organization uses.Keep up with OpenAI API without adding it to your stack.Visit Website
Operating stack
AI Application Platform

Models

Which models does OpenAI API serve, and where is each strong?

Each model's page charts its public benchmark scores beside any other model you layer on it.

  1. GPT-6 AstraOpenAI's highest-capability GPT-6 release for complex end-to-end work.GPT AstraBenchmarks
  2. GPT-6.1 SolOpenAI's newer Sol model, close to GPT-6 Astra on complex work at a lower cost. On OpenAI's own OSWorld 2.1 computer-use run (offline set) it scores 78%, 2.9 points under GPT-6 Astra at about a seventh of the cost per task. API model gpt-6.1-sol, with a 1,050,000-token context on the OpenAI API; Microsoft Foundry caps input at 922,000 tokens.GPT SolBenchmarks
  3. GPT-6 LunaOpenAI's most efficient GPT-6 model, for focused, high-volume tasks. API model gpt-6-luna, with a 1,050,000-token context on the OpenAI API; Microsoft Foundry caps input at 922,000 tokens.GPT LunaBenchmarks
  4. GPT-6.1 TerraOpenAI's fast, efficient GPT-6.1 model for visual reasoning, computer use and writing, at US$1 per million input tokens and US$5 per million output tokens. Artificial Analysis scores it 51 on its Intelligence Index at US$0.96 per task, and OpenAI's own OSWorld 2.1 computer-use run (offline set) puts it at 74.2%, 3.8 points under GPT-6.1 Sol. API model gpt-6.1-terra, with a 1,050,000-token context and 128,000 output tokens on the OpenAI API.GPT TerraBenchmarks
  5. GPT-5.6 SolOpenAI's GPT-5.6 flagship model for complex professional work, with text and image input. API model gpt-5.6-sol at US$4 per million input tokens and US$20 per million output tokens, with a 1,050,000-token context window and 128,000 output tokens; also in GitHub Copilot and Cursor.GPT SolBenchmarks
  6. GPT-5.6 TerraOpenAI's GPT-5.6 model that balances intelligence and cost, with text and image input. API model gpt-5.6-terra at US$2 per million input tokens and US$12 per million output tokens, with a 1,050,000-token context window; also in GitHub Copilot and Cursor.GPT TerraBenchmarks
  7. GPT-5.6 LunaOpenAI's GPT-5.6 model for cost-sensitive, high-volume workloads, with text and image input. API model gpt-5.6-luna at US$0.20 per million input tokens and US$1.20 per million output tokens, with a 1,050,000-token context window; also in GitHub Copilot and Cursor.GPT LunaBenchmarks
  8. GPT-5.5OpenAI's GPT-5.5 flagship model for coding and complex professional work, with text and image input. API model gpt-5.5 (snapshot gpt-5.5-2026-04-23) at US$5 per million input tokens and US$30 per million output tokens, with a 1,050,000-token context window; also in Cursor. It left GitHub Copilot on October 19, 2026 and Codex for ChatGPT sign-in on October 14, 2026.GPT-5Benchmarks
  9. GPT-5.4OpenAI's GPT-5.4 model for coding and professional work, with text and image input. API model gpt-5.4 (snapshot gpt-5.4-2026-03-05) at US$2.50 per million input tokens and US$15 per million output tokens, with a 1,050,000-token context window; prompts over 272K input tokens cost more. Also in Cursor; GitHub Copilot dropped it on October 19, 2026.GPT-5Benchmarks

Comparisons

How does OpenAI API compare with the alternatives?

See all 4 comparisons

  1. OpenAI API vs Claude API

    • AI Model APIs

    GPT-6.1 Sol scores 55 on the Artificial Analysis Intelligence Index v5.0 (Oct 27, 2026) at US$1.27 per task, against US$10.02 for Sonnet 5.5 at the same list price, while Opus 5.5 holds the top score. Test both with caching on.

  2. OpenAI API vs Gemini API

    • AI Model APIs

    Wealthsimple and DoorDash run both behind one gateway. GPT-6.1 Sol outscores Gemini 4 Argon and Gemini 3.8 Flash on the Artificial Analysis Intelligence Index v5.0 (Oct 27, 2026) at a lower cost per task, and Argon's introductory price ends on November 30, 2026.

  3. OpenAI API vs Azure OpenAI

    • AI Model APIs
    • Governance

    DoorDash and Grab keep Azure OpenAI as a second route to the same models. Buy from OpenAI for release-day features and a hard spend cap; choose Azure OpenAI when your Microsoft contract or data processor rules decide it.

Operator Insights

What are teams learning from building on OpenAI API and running it in production?

See all 9 operator accounts

Buying and deployment

What a team building on it should verify before production traffic grows.

Sourced from OpenAI documentation

How you buy it

US$2 in, US$10 out

Per million tokens for GPT-6.1 Sol. Luna is US$0.10 and US$0.50, Astra US$10 and US$50.

Source 1, OpenAI, Pricing: PricingSource 2, OpenAI, Rate limits: Rate limits

Details

Usage based, per million tokens in US dollars on prepaid credits. For prompts up to 272,000 tokens, GPT-6 Luna US$0.10 input and US$0.50 output. GPT-6.1 Sol US$2 and US$10. GPT-6 Astra US$10 and US$50. Scale Tier and Reserved Tier sell more predictable capacity.

Cost drivers

Batch halves it

Batch and Flex halve prices. Cache reads are 5% of input on GPT-6.1 Sol and Terra, 10% on most others.

Source 1, OpenAI, Pricing: PricingSource 5, developers.openai.com, GPT-6.1 Sol model page: GPT-6.1 Sol model pageSource 6, developers.openai.com, API changelog: API changelog

Details

Model choice and output tokens, including reasoning, drive cost. Prompts over 272,000 input tokens cost 2x input and 1.5x output. Cache reads cost a tenth of the input rate on most models, or 5% on GPT-6.1 Sol and GPT-6.1 Terra. Writes cost 1.25x for the default 30-minute cache, or 2.5x for a 12-hour cache since October 20, 2026. Batch and Flex halve prices. Fast mode doubles them, and regional processing adds 10%.

Where it runs

US, EU, UAE

Regional processing options. Azure and Bedrock also run GPT-6 and bill on their own.

Source 3, OpenAI, Data controls: Data controlsSource 7, azure.microsoft.com, Azure OpenAI pricing (Microsoft): Azure OpenAI pricing (Microsoft)Source 8, Amazon Web Services, Amazon Bedrock pricing (AWS): Amazon Bedrock pricing (AWS)

Details

OpenAI offers regional processing in the US, the EU, and the UAE, plus storage-only residency in seven more regions for eligible projects. Microsoft Azure and Amazon Bedrock also run GPT-6 models and bill through their own services.

What to verify

US$500 to US$200,000

The monthly usage cap, from the Build tier to Grow. Models have published shutdown dates.

Source 2, OpenAI, Rate limits: Rate limitsSource 3, OpenAI, Data controls: Data controlsSource 4, OpenAI, Deprecations: Deprecations

Details

Usage tiers cap monthly usage, from US$500 on Build to US$200,000 on Grow, and set per-model rate limits. Zero Data Retention eligibility depends on the endpoint. Batch and the Agents API keep application state. Models have published shutdown dates.

Signals

What is the current evidence saying about OpenAI API?

A current read of what teams and builders running OpenAI models through the API, Azure OpenAI, and Amazon Bedrock report publicly, with each finding linked to its sources.

Whose sources count

Practitioner sentiment, teams and leaders

+3 Mixed net

of 65 sources that take a side, each author counted once.

How this figure is made

Current sentiment

Positive, mixed and negative sources

The score counts them as 21 positive, 22 mixed and 19 negative votes, one per author.

Teams and leaders split close to evenly: 22 positive, 23 mixed and 20 negative. They praise model quality most, then cost efficiency. Latency leads their concerns, followed by token cost and inconsistent results, and DoorDash, Grab and Wealthsimple each run OpenAI beside other providers behind one gateway.

Run a pilot on your own prompts to measure output quality and cost per task.

Evidence field. All 154 sources, one mark each.

Arrange by

Each mark is one source: positive, mixed, negative, no opinion stated, or documentation (not counted).

By sentiment, Teams and technical leaders. Every source GILD read, grouped as the field draws it.
GroupSourcesPositiveMixedNegativeNo opinion stated and not counted in the scoreDocumentation, checked and not counted
Positive22220000
Mixed23023000
Negative20002000
Not counted10000100
Documentation18000018
Outside this group6121209110
Every source GILD read, by the quarter it was published, as the field's time axis counts it. Documentation is dated by the day it was checked.
QuarterSources
Q1 202511
Q2 202520
Q3 202514
Q4 202513
Q1 20269
Q2 202610
Q3 202634
Q4 202625
Documentation, checked18

By sentiment

18 documentation pages check facts and are not counted; 61 sit outside this group.

Hover a mark for a quick look, click it or press Enter to open its source.Tap a mark to open its source, then step to its neighbors with Previous and Next.

What practitioners praise

Top praise of 5. Each mark is a source on it; filled marks praise it.

  1. Model Quality14 of 18 sources on it praise it

Most common concerns

Top concern of 8. Each mark is a source on it; filled marks raise it.

  1. Latency9 of 12 sources on it raise it as a concern
All 154 sources behind these findings
  1. Hacker News comment on GPT-6.1 Terra for agentic production__jl__, Hacker News commenter (self-described: An application running almost entirely on the OpenAI API, with fallback models), Hacker News comment, published Oct 26, 2026
  2. X post on OpenAI API 429 errors during capacity issuesSonofpeace0001, X (self-described: An agent builder running multi-step work on the OpenAI API), X post, published Oct 26, 2026
  3. X post on OpenAI's 12-hour prompt cacheAndrew Hickl, CTO, Allen Institute (X profile) (self-described: Agents that wake a few times a day on the same context), X post, published Oct 26, 2026
  4. Why are some GPT 5 API requests costing three times more than others?Swimming-Skirt3870, Reddit (r/OpenAI) (self-described: Document processing on the GPT-5 API), Reddit post, r/OpenAI, published Oct 24, 2026
  5. One compromised project, entire OpenAI account closedSouth_Traffic_72, Reddit (r/OpenAIDev) (self-described: A developer building about 20 client projects on the OpenAI API), Reddit post, r/OpenAIDev, published Oct 23, 2026
  6. Using OpenAI Realtime API with a RobotTarun122, Reddit (r/OpenAI) (self-described: A personal robot arm driven by voice), Reddit post, r/OpenAI, published Oct 23, 2026
  7. API Credit expiry - another yearkeithmifsud, Reddit (r/OpenAI) (self-described: Prepaid OpenAI API credits bought for a team), Reddit post, r/OpenAI, published Oct 21, 2026
  8. Reply on API billing errors, r/OpenAIjkos123, Reddit (r/OpenAI) (self-described: OpenAI API account billing), Reddit comment, r/OpenAI, published Oct 20, 2026
  9. Is anyone building on the Agents API yet?apricot_dragon, Reddit (r/OpenAI) (self-described: An agent backend moved onto OpenAI's Agents API (beta)), Reddit post, r/OpenAI, published Oct 20, 2026
  10. Reply on ChatGPT credits and API billing, r/OpenAIChoiceAnalyst1599, Reddit (r/OpenAI) (self-described: Setting up OpenAI API billing), Reddit comment, r/OpenAI, published Oct 19, 2026
  11. openai-python issue #4090: streaming helpers re-parse accumulated JSONdeadstrobe5, GitHub issue author (self-described: Streaming structured outputs and strict tool calls in openai-python), GitHub issue, openai/openai-python, published Oct 16, 2026
  12. Beyond the leaderboard. Decision models in a real workflow.Prasanth Jayachandran, Isotopes AI (self-described: Isotopes AI aidnn follow-up workflow, 88 scenarios run three times per model under zero data retention), Engineering blog post, Isotopes AI blog, published Oct 15, 2026
  13. PricingOpenAI (Official OpenAI API documentation), Product documentation, checked Oct 12, 2026
  14. ModelsOpenAI (Official OpenAI API documentation), Product documentation, checked Oct 12, 2026
  15. GPT-6 LunaOpenAI (Official OpenAI API documentation), Product documentation, checked Oct 12, 2026
  16. Rate limitsOpenAI (Official OpenAI API documentation), Product documentation, checked Oct 12, 2026
  17. Spend limitsOpenAI (Official OpenAI API documentation), Product documentation, checked Oct 12, 2026
  18. Prompt cachingOpenAI (Official OpenAI API documentation), Product documentation, checked Oct 12, 2026
  19. Batch APIOpenAI (Official OpenAI API documentation), Product documentation, checked Oct 12, 2026
  20. Flex processingOpenAI (Official OpenAI API documentation), Product documentation, checked Oct 12, 2026
  21. Fast modeOpenAI (Official OpenAI API documentation), Product documentation, checked Oct 12, 2026
  22. Data controls in the OpenAI platformOpenAI (Official OpenAI API documentation), Product documentation, checked Oct 12, 2026
  23. DeprecationsOpenAI (Official OpenAI API documentation), Product documentation, checked Oct 12, 2026
  24. Migrate to the Responses APIOpenAI (Official OpenAI API documentation), Product documentation, checked Oct 12, 2026
  25. AgentsOpenAI (Official OpenAI API documentation), Product documentation, checked Oct 12, 2026
  26. Agents APIOpenAI (Official OpenAI API documentation), Product documentation, checked Oct 12, 2026
  27. MCP serversOpenAI (Official OpenAI API documentation), Product documentation, checked Oct 12, 2026
  28. Latency optimizationOpenAI (Official OpenAI API documentation), Product documentation, checked Oct 12, 2026
  29. OpenAI on Amazon BedrockOpenAI (Official OpenAI API documentation), Product documentation, checked Oct 12, 2026
  30. Evaluation best practicesOpenAI (Official OpenAI API documentation), Product documentation, checked Oct 12, 2026
  31. Comment on: Why isn't the industry freaking out about DeepSeek 4.1 Flash?epolanski, Hacker News commenter (self-described: Consultant describing client procurement), Hacker News comment, published Oct 9, 2026
  32. Comment on: Claude Haiku 5.5Farmadupe, Hacker News commenter (self-described: Own classification workload), Hacker News comment, published Oct 8, 2026
  33. How we cut a browser agent's cost 76x and made it 5x faster by keeping its cache intactFrank Hidalgo, CTO of StackAI, Asana (self-described: Asana's StackAI browser agent, tested across four frontier models in a 144-run caching study), Engineering blog, Inside Asana, published Oct 8, 2026
  34. Decision vs execution: a pattern for using GPT safely inside RPA pipelinesAbiram, OpenAI Developer Forum (self-described: Enterprise finance team adding LLM steps to UiPath and Power Automate bots), OpenAI Developer Forum post, published Oct 7, 2026
  35. Comment on: Decisions API is in public betaelpakal, Hacker News commenter (self-described: Team on Amazon Bedrock), Hacker News comment, published Oct 7, 2026
  36. Comment on: Claude Haiku 5.5Topfi, Hacker News commenter (self-described: Own model comparisons), Hacker News comment, published Oct 7, 2026
  37. Comment on: Claude Haiku 5.5mrbungie, Hacker News commenter (self-described: Own zero-shot and few-shot tasks), Hacker News comment, published Oct 7, 2026
  38. Long Responses API runs are costing us more from context than the output itselfImmediate_Menu_3695, Reddit (r/OpenAI) (self-described: A multi-step, tool-using workflow on the Responses API), Reddit post, r/OpenAI, published Oct 7, 2026
  39. Has anyone managed to get EU data residency on their API account?Suitable-Season-4847, Reddit (r/OpenAI) (self-described: A UK SaaS platform with public sector customers), Reddit post, r/OpenAI, published Oct 5, 2026
  40. Building a GenAI Platform at DoorDashSiddharth Kodwani, Software Engineer, GenAI Platform, DoorDash (self-described: DoorDash's LLM Gateway, which serves OpenAI, Anthropic and Gemini models to product teams across the company), Conference talk, InfoQ, published Oct 3, 2026
  41. Comment on: The OpenAI Decisions API needs a confidence you can trustbob1029, Hacker News commenter (self-described: Client projects on the API), Hacker News comment, published Oct 2, 2026
  42. openai-python issue #4020: Responses request transform CPU costzdurm, GitHub issue author (self-described: The openai-python SDK on the Responses API), GitHub issue, openai/openai-python, published Oct 2, 2026
  43. Does anyone separate OpenAI Batch spend from normal API spend internally?No_Refrigerator_8216, Reddit (r/OpenAI) (self-described: A team running both live API traffic and Batch jobs), Reddit post, r/OpenAI, published Oct 2, 2026
  44. Free the models: Harness design at the frontierDaniel Furman, Jacky Zhao, Vaibhav Kumar, Ed Sioufi, and Michele Catasta, Replit (self-described: Replit Agent in Max mode with GPT-6 Astra as the core loop), Engineering blog post, Replit blog, published Sep 29, 2026
  45. GPT-6.1 Sol is now available in DevinCognition, the team behind Devin (self-described: Devin, models graded on Cognition's FrontierCode benchmark of real engineering tasks), Company blog post, Devin blog, published Sep 29, 2026
  46. The best LLM writes correct Elasticsearch ES|QL 59% of the time. Here's what breaks the other 41%.Jeffrey Rengifo and Gustavo Llermaly, Elastic (self-described: Elasticsearch Labs test of 500 BIRD questions per model for generated ES|QL queries), Engineering blog post, Elasticsearch Labs, published Sep 28, 2026
  47. Comment on: GPT-6 Sol and Lunaanelson, Hacker News commenter (self-described: Cybersecurity application with internal evals), Hacker News comment, published Sep 26, 2026
  48. Comment on: GPT-6 Sol and Lunabuckwheatmilk, Hacker News commenter (self-described: Own structured-output task), Hacker News comment, published Sep 23, 2026
  49. Show HN reply on a podcast-archive pipeline's costssnow_mac, Hacker News commenter (self-described: A personal pipeline that transcribes, summarizes and indexes 230 podcast episodes), Hacker News comment, published Sep 23, 2026
  50. gpt-realtime-2.1: production tool invocation regressionWebPlanning SIM-Ltd, OpenAI Developer Forum (self-described: WebPlanning SIM-Ltd, production voice agent), OpenAI Developer Forum post, published Sep 17, 2026
  51. Shipped a voice agent on the Realtime API: 7 behavioral bugs from production call logsauthentic_developer, Reddit (r/OpenAI) (self-described: A business voice agent on the Realtime API, in production for a few months), Reddit post, r/OpenAI, published Sep 14, 2026
  52. Comment on: OpenAI Agents APIdools, Hacker News commenter (self-described: Internal agent app used by colleagues), Hacker News comment, published Sep 11, 2026
  53. Comment on: OpenAI Agents APIz2, Hacker News commenter (self-described: Own model integrations), Hacker News comment, published Sep 11, 2026
  54. Comment on: OpenAI Agents APIbaalimago, Hacker News commenter (self-described: Own agent with sandbox and Slack integrations), Hacker News comment, published Sep 11, 2026
  55. Comment on: OpenAI Agents APIeverlier, Hacker News commenter (self-described: Company workflows on the API), Hacker News comment, published Sep 10, 2026
  56. Comment on: Claude outage - Resolvedeis, Hacker News commenter (self-described: Team product with a fallback provider), Hacker News comment, published Sep 3, 2026
  57. Comment on: GPT-5.6 Sol Pricing Cut by 50% on OpenRouterpimeys, Hacker News commenter (self-described: Agent company's production systems), Hacker News comment, published Aug 18, 2026
  58. Comment on: GPT-5.6 Sol Pricing Cut by 50% on OpenRouterSyneRyder, Hacker News commenter (self-described: Own routing through OpenRouter), Hacker News comment, published Aug 18, 2026
  59. Comment on: GPT-5.6 Sol Pricing Cut by 50% on OpenRouterxmonkee, Hacker News commenter (self-described: Own work with sensitive data), Hacker News comment, published Aug 17, 2026
  60. Our OpenAI bill tells us what we spent, not who spent itAccountEngineer, Reddit (r/LLMDevs) (self-described: An AI SaaS company with about 40 customers), Reddit post, r/LLMDevs, published Aug 16, 2026
  61. Problem with tool_choice causing caching issuesKingston Duffie, OpenAI Developer Forum (self-described: Production system using function tools on GPT-5.6 through the Responses API), OpenAI Developer Forum post, published Aug 15, 2026
  62. Comment on: Gemini 3.7 FlashEB66, Hacker News commenter (self-described: Company in-house LLM benchmarks), Hacker News comment, published Aug 14, 2026
  63. Please Don't Deprecate GPT-Realtime Before a True Replacement Existscarlos_ds, OpenAI Developer Forum (self-described: Production outbound voice agent for structured telephony calls), OpenAI Developer Forum post, published Aug 4, 2026
  64. Comment on: Advancing the price-performance frontier with GPT‑5.6dannyw, Hacker News commenter (self-described: Own pay-per-token API use), Hacker News comment, published Jul 31, 2026
  65. Comment on: Advancing the price-performance frontier with GPT‑5.6__jl__, Hacker News commenter (self-described: Team production app), Hacker News comment, published Jul 30, 2026
  66. Comment on: Launch HN: Bloomy (YC S26) - AI-powered mastery learning for K-12alexsouthmayd, Hacker News commenter (self-described: Bloomy, K-12 learning platform), Hacker News comment, published Jul 21, 2026
  67. OpenAI says I must switch to prepaid API billing, but the option is missingancestralsimulation, Reddit (r/OpenAIDev) (self-described: Several production mobile apps on one API organization), Reddit post, r/OpenAIDev, published Jul 18, 2026
  68. Comment on: Migrating a production AI agent to GPT-5.6: 2.2x faster, 27% cheapermadaxe_again, Hacker News commenter (self-described: Text and image extraction workflows in production), Hacker News comment, published Jul 13, 2026
  69. Prompt Caching Is a Core GPT-5.6 Feature. Why Are Customers Still Reverse-Engineering It?Sai Reddy, OpenAI Developer Forum (self-described: Team running GPT-5.6 Sol on Azure OpenAI), OpenAI Developer Forum post, published Jul 12, 2026
  70. GPT-5.6: usage.output_tokens is ~9x actual generationBen B, OpenAI Developer Forum (self-described: ChessBench, a benchmark that runs chess games between models), OpenAI Developer Forum post, published Jul 11, 2026
  71. Comment on: GPT-5.6pimeys, Hacker News commenter (self-described: Agent company running evals), Hacker News comment, published Jul 10, 2026
  72. Comment on: Please don't discontinue Gemini 2.5 Flashdacox, Hacker News commenter (self-described: Team fine-tuned workloads), Hacker News comment, published Jul 10, 2026
  73. Comment on: GPT-5.6XCSme, Hacker News commenter (self-described: Own n8n automations and benchmark site), Hacker News comment, published Jul 9, 2026
  74. Migrating a production AI agent to GPT-5.6Lorenzo Gentile, Ploy engineering blog (self-described: Ploy, production agent that builds and edits marketing websites), Engineering blog post, Ploy blog, published Jul 9, 2026
  75. GPT-5.6 Luna (Max) Intelligence, Performance & Price AnalysisArtificial Analysis, independent model benchmarking service (self-described: Standard 10,000-input-token workload on OpenAI's API), Independent benchmark, Artificial Analysis, published Jul 9, 2026
  76. Prompt caching returns cached_tokens=0 intermittently (same static prefix, same prompt_cache_key)benlyazid, OpenAI Developer Forum (self-described: Multi-agent system on the OpenAI API with a per-tenant cache key), OpenAI Developer Forum post, published Jul 8, 2026
  77. Comment on: GPT-5.6 Sol Ultra will be in CodexSwellJoe, Hacker News commenter (self-described: Own benchmarks), Hacker News comment, published Jul 6, 2026
  78. Comment on: Previewing GPT-5.6 Sol: a next-generation modelHyperL0gi, Hacker News commenter (self-described: Own workloads on GPT-5 mini), Hacker News comment, published Jun 26, 2026
  79. Comment on: RubyLLM: A Ruby framework for all major AI providersMitziMoto, Hacker News commenter (self-described: Team product built on RubyLLM), Hacker News comment, published Jun 24, 2026
  80. Voice AI & Voice Agents: An Illustrated PrimerKwindla Hultman Kramer, CEO, Daily (Daily and the Pipecat open-source framework for production voice agents), Technical guide, voiceaiandvoiceagents.com, published Jun 1, 2026
  81. Comment on: Ask HK: How are you building AI apps today?sibidharan, Hacker News commenter (self-described: EdTech product with AI learning tools), Hacker News comment, published May 29, 2026
  82. Zero Data Retention (ZDR) request: enterprise customer, no response after multiple submissionsShane Prebenda, OpenAI Developer Forum (self-described: Production platform whose client NDAs require Zero Data Retention), OpenAI Developer Forum post, published May 27, 2026
  83. Cross-provider API cost allocation at team scaleNoTextit, Reddit (r/LLMDevs), runs platform engineering at a 150-person company (self-described: Platform engineering at a 150-person company, about 80 people using the API), Reddit post, r/LLMDevs, published May 19, 2026
  84. Comment on: OpenAI models coming to Amazon Bedrock: Interview with OpenAI and AWS CEOs7thpower, Hacker News commenter (self-described: Team that ran OpenAI models on Azure two to three years earlier), Hacker News comment, published Apr 29, 2026
  85. Comment on: OpenAI models coming to Amazon Bedrock: Interview with OpenAI and AWS CEOsFoobar8568, Hacker News commenter (self-described: Team that ran Azure OpenAI deployments until about a year earlier), Hacker News comment, published Apr 29, 2026
  86. Sudden increase in /v1/responses timeouts on gpt-4.1-mini (stable for months, started recently)lastround360, OpenAI Developer Forum (self-described: Mobile app calling the Responses API through a Supabase Edge Function), OpenAI Developer Forum post, published Apr 19, 2026
  87. Calories & Macros LLM estimates from text (simple meals) comparison between frontier labsAndreiOnyx, r/LLMDevs (self-described: Calorie tracking app, benchmark before choosing a model), Reddit post, published Apr 7, 2026
  88. Comment on: The first 40 months of the AI eraeloisius, Hacker News commenter (self-described: Consulting on a client's agentic features), Hacker News comment, published Mar 29, 2026
  89. Comment on: GPT‑5.4 Mini and Nanoilaksh, Hacker News commenter (self-described: Own voice applications), Hacker News comment, published Mar 17, 2026
  90. Comment on: GPT‑5.4 Mini and NanoRapzid, Hacker News commenter (self-described: Own latency-sensitive workloads), Hacker News comment, published Mar 17, 2026
  91. Comment on: GPT‑5.4 Mini and Nanopscanf, Hacker News commenter (self-described: Own agentic applications), Hacker News comment, published Mar 17, 2026
  92. 5 LLM APIs Tested for Latency: Real Data [2026]Kunal Ganglani, independent AI engineer (Streaming benchmark from one Toronto server, plus a year of production workloads across three providers), Independent benchmark, personal blog, published Mar 7, 2026
  93. Comment on: GPT-5.4lmeyerov, Hacker News commenter (self-described: Team evals on cybersecurity investigations), Hacker News comment, published Mar 5, 2026
  94. GPT-5.4, The New OracleAmp team, Amp (self-described: Amp coding agent, GPT-5.4 as the oracle subagent in smart and deep modes), Product engineering post, Amp Chronicle, published Mar 5, 2026
  95. The Limits of Long-Context Reasoning in Automated Bug FixingRavi Raju and four coauthors (self-described: Academic evaluation of patch generation on SWE-bench Verified, in an agent harness and with files placed in a 64K-token context), Research paper, arXiv (ICLR 2026 ICBINB workshop), published Feb 17, 2026
  96. GPT-5 vs Other LLMs in Long Short-Context PerformanceNima Esmi and coauthors, University of Groningen, University of Guilan, and TU Delft (self-described: Academic evaluation of GPT-5, GPT-4, Gemini 2.5, and Grok-4 on a 20,000-post classification set), Research paper, arXiv (FLLM 2025, IEEE), published Feb 15, 2026
  97. LLMs Are Cheap Enough to Change How You Work With DataDumky de Wilde, independent developer (self-described: Backfill of job postings for selectfrom.work), Personal blog post, dumky.net, published Dec 21, 2025
  98. Comment on: Gemini 3 Flash: Frontier intelligence built for speedmips_avatar, Hacker News commenter (self-described: Own applications that need low latency), Hacker News comment, published Dec 17, 2025
  99. Comment on: GPT-5.2sigmoid10, Hacker News commenter (self-described: Team on OpenAI's highest enterprise tier), Hacker News comment, published Dec 12, 2025
  100. Stochasticity in Agentic Evaluations: Quantifying Inconsistency with Intraclass CorrelationZairah Mustahsan, Abel Lim, Megna Anand, Saahil Jain, and Bryan McCann, You.com (self-described: You.com research team running 64 trials per question on GAIA and FRAMES), Research paper, arXiv, published Dec 7, 2025
  101. Comment on: Claude Opus 4.5consumer451, Hacker News commenter (self-described: Side projects on several model APIs), Hacker News comment, published Nov 24, 2025
  102. Comment on: Show HN: I built CostLens SDK to cut my AI bills by routing to cheaper modelsj_filipe, Hacker News commenter (self-described: Own production apps), Hacker News comment, published Nov 16, 2025
  103. Comment on: Structured outputs on the Claude Developer Platformmparis, Hacker News commenter (self-described: Team running structured outputs in production), Hacker News comment, published Nov 14, 2025
  104. Comment on: GPT-5.1: A smarter, more conversational ChatGPTrcarmo, Hacker News commenter (self-described: Personal OpenWebUI setup on Azure OpenAI), Hacker News comment, published Nov 13, 2025
  105. Comment on: Claude Haiku 4.5Topfi, Hacker News commenter (self-described: Own model evaluations), Hacker News comment, published Oct 16, 2025
  106. Comment on: Claude Haiku 4.5tempusalaria, Hacker News commenter (self-described: Own production workloads, details withheld), Hacker News comment, published Oct 16, 2025
  107. Comment on: Claude Haiku 4.5pietz, Hacker News commenter (self-described: Company workflows: extraction, conversion, translation, evaluation), Hacker News comment, published Oct 15, 2025
  108. How to become eligible for data residency endpoints?Michal Stoklasa, OpenAI Developer Forum (self-described: AI web agent company with about 70 larger customers in Europe), OpenAI Developer Forum post, published Oct 13, 2025
  109. GPT-5 OracleAmp team, Amp (self-described: Amp coding agent, GPT-5 as the oracle subagent beside Sonnet as the main agent model), Product engineering post, Amp Chronicle, published Oct 1, 2025
  110. Comment on: Sampling and structured outputs in LLMshedgehog, Hacker News commenter (self-described: Team with its own prompt templates and schema definitions), Hacker News comment, published Sep 23, 2025
  111. Cost of Serving LLMsStefan Ivanovici, Intercom (self-described: Intercom's Fin customer support agent, self-hosted open-weight models compared with provider APIs), Engineering research post, Fin AI research blog, published Sep 10, 2025
  112. Comment on: Adaptive LLM routing under budget constraintsdahcryn, Hacker News commenter (self-described: Team running AI features in production), Hacker News comment, published Sep 2, 2025
  113. GPT-5 Coding Evaluation: Underwhelming Performance Given the HypeZhu Liang, creator of 16x Eval (self-described: 16x Eval's own set of six coding tasks, run through the OpenAI API at default settings), Independent benchmark, 16x Eval blog, published Aug 15, 2025
  114. Comment on: Launch HN: Cyberdesk (YC S25) - Automate Windows legacy desktop appsmahmoud-almadi, Hacker News commenter at Cyberdesk (self-described: Cyberdesk, healthcare desktop automation), Hacker News comment, published Aug 14, 2025
  115. Feedback: GPT-5 vs GPT-5-Chat-Latest for Conversational AIDobo Radichkov, OpenAI Developer Forum (self-described: Onsen, AI mental health companion app), OpenAI Developer Forum post, published Aug 10, 2025
  116. Comment on: GPT-5 for Developersenergy123, Hacker News commenter (self-described: Own coding questions on the API), Hacker News comment, published Aug 8, 2025
  117. Comment on: GPT-5 on SWE-bench: Cost and performance deep-divelieret, Hacker News commenter (self-described: SWE-bench team evaluating models with a minimal agent), Hacker News comment, published Aug 8, 2025
  118. Comment on: GPT-5 for Developerspotatolicious, Hacker News commenter (self-described: Tool-heavy systems at work), Hacker News comment, published Aug 7, 2025
  119. GPT-5: Key characteristics, pricing and model cardSimon Willison, independent developer and creator of the LLM command-line tool (self-described: Two weeks of daily use of GPT-5 through the API and his own LLM tool), Personal blog post, simonwillison.net, published Aug 7, 2025
  120. Comment on: Claude Opus 4.1bayesianbot, Hacker News commenter (self-described: Own agentic workloads), Hacker News comment, published Aug 6, 2025
  121. Comment on: The Intelligence HubJacob-J-Thomas, Hacker News commenter (self-described: Enterprise chat app on Azure OpenAI, two years earlier), Hacker News comment, published Jul 23, 2025
  122. Comment on: Batch Mode in the Gemini API: Process More for Lessdruskacik, Hacker News commenter (self-described: Own batch workloads), Hacker News comment, published Jul 11, 2025
  123. Experience and opinion on 4 APIs (assistant, chat completions, responses, realtime)johnroy, OpenAI Developer Forum (self-described: Startup founder building on four OpenAI APIs over 18 months), OpenAI Developer Forum post, published Jul 3, 2025
  124. Comment on: ChatGPT's enterprise success against Copilot fuels OpenAI/Microsoft rivalryBrandiATMuhkuh, Hacker News commenter (self-described: Co-pilot product for architects (AEC)), Hacker News comment, published Jun 25, 2025
  125. NYT lawsuit and 30 days data retentionHerman, OpenAI Developer Forum (self-described: Swedish company whose customers need retention under 30 days), OpenAI Developer Forum post, published Jun 16, 2025
  126. Comment on: OpenAI dropped the price of o3 by 80%jacob019, Hacker News commenter (self-described: Own day-to-day API use), Hacker News comment, published Jun 10, 2025
  127. Comment on: How we're responding to The NYT's data demands in order to protect user privacymolf, Hacker News commenter (self-described: Business API customer applying for Zero Data Retention), Hacker News comment, published Jun 6, 2025
  128. Comment on: New tools and features in the Responses APIjasongill, Hacker News commenter (self-described: Team product on the Assistants API), Hacker News comment, published May 21, 2025
  129. Comment on: New tools and features in the Responses APIalasano, Hacker News commenter (self-described: MVP product), Hacker News comment, published May 21, 2025
  130. Comment on: New tools and features in the Responses APImritchie712, Hacker News commenter at Definite (self-described: Definite, data platform agent), Hacker News comment, published May 21, 2025
  131. Comment on: The unreasonable effectiveness of an LLM agent loop with tool usejbellis, Hacker News commenter at Brokk (self-described: Brokk, search and architect agents), Hacker News comment, published May 15, 2025
  132. Expanding Harvey's Model OfferingsHarvey Team, Harvey (self-described: Harvey legal AI platform, adding Anthropic and Google models beside its OpenAI models), Company blog post, Harvey blog, published May 13, 2025
  133. LongCodeBench: Evaluating Coding LLMs at 1M Context WindowsStefano Rando and seven coauthors (self-described: Academic coding benchmark of code questions and bug fixes on real repositories at contexts up to 1M tokens), Research paper, arXiv, published May 12, 2025
  134. Comment on: Ask HN: How much better are AI IDEs vs. copy pasting into chat apps?PeterStuer, Hacker News commenter (self-described: Own production systems on the API), Hacker News comment, published May 8, 2025
  135. Comment on: Google Gemini has the worst LLM APIsimonw (Simon Willison), Hacker News commenter (self-described: Own LLM tools and apps), Hacker News comment, published May 4, 2025
  136. Increased latency on GPT-4.1 Mini over the past few daysEduardo Stuani, OpenAI Developer Forum (self-described: Latency-critical application with 110K-token cached prompts), OpenAI Developer Forum post, published Apr 30, 2025
  137. Comment on: Show HN: Daily Jailbreak - Prompt Engineer's Wordleericlmtn, Hacker News commenter (self-described: Daily prompt game), Hacker News comment, published Apr 27, 2025
  138. Comment on: OpenAI releases image generation in the APIWowfunhappy, Hacker News commenter (self-described: Own API account), Hacker News comment, published Apr 24, 2025
  139. GPT-4.1 and o4-mini: Is OpenAI Overselling Long-Context?Daniel Chalef, founder and CEO of Zep, with Preston Rasmussen, Zep (self-described: Zep, a memory service for AI agents, benchmarking OpenAI models on LongMemEval), Engineering blog post, Zep blog, published Apr 17, 2025
  140. Comment on: OpenAI o3 and o4-minijumploops, Hacker News commenter at Magic Loops (self-described: Own agent tests), Hacker News comment, published Apr 16, 2025
  141. Comment on: GPT-4.1 in the APIpcwelder, Hacker News commenter (self-described: Own agent tests), Hacker News comment, published Apr 14, 2025
  142. GPT-4.1: Three new million token input models from OpenAI, including their cheapest model yetSimon Willison, independent developer and creator of the LLM command-line tool (self-described: Testing the GPT-4.1 family through his llm-openai plugin on launch day), Personal blog post, simonwillison.net, published Apr 14, 2025
  143. We benchmarked GPT-4.1 vs Claude 3.7: Here's what we foundDedy Kredo, Qodo (self-described: Qodo code review product), Engineering blog post, Qodo blog, published Apr 13, 2025
  144. My experience switching from Assistants API to Responses APIKingston Duffie, OpenAI Developer Forum (self-described: Production RAG chat application with tens of thousands of users), OpenAI Developer Forum post, published Mar 22, 2025
  145. Comment on: OpenAI's o1-pro now available via APIsimonw (Simon Willison), Hacker News commenter (self-described: Own open-source LLM tool), Hacker News comment, published Mar 19, 2025
  146. Comment on: Ask HN: AI infrastructure in production - what is your tech stack?k9294, Hacker News commenter (self-described: Startup with a few thousand monthly active users), Hacker News comment, published Mar 17, 2025
  147. Comment on: New tools for building agentsdaviding, Hacker News commenter (self-described: Team assistant built on Chat Completions), Hacker News comment, published Mar 12, 2025
  148. Comment on: New tools for building agentssagarpatil, Hacker News commenter (self-described: Several agents in production), Hacker News comment, published Mar 12, 2025
  149. Comment on: New tools for building agentsbob1029, Hacker News commenter (self-described: Own products built on the API), Hacker News comment, published Mar 11, 2025
  150. Comment on: New tools for building agentssippeangelo, Hacker News commenter (self-described: Own applications), Hacker News comment, published Mar 11, 2025
  151. Grab AI Gateway: Connecting Grabbers to multiple GenAI providersSiddharth Pandey and Wenbo Wei, Grab engineering (self-described: Grab's company AI Gateway, a set of reverse proxies to Azure, OpenAI, AWS and other providers), Engineering blog, Grab Tech, published Feb 19, 2025
  152. NoLiMa: Long-Context Evaluation Beyond Literal MatchingAli Modarressi and six coauthors (self-described: Academic long-context benchmark of 13 models, with questions and needles that share minimal wording), Research paper, arXiv (ICML 2025), published Feb 7, 2025
  153. Gen AI productivity tools at WealthsimpleMandy Gu, author of the InfoQ article on Wealthsimple's platform (self-described: Wealthsimple's internal LLM gateway, which started with OpenAI and Cohere and later added Gemini and Amazon Bedrock), Engineering article, InfoQ, published Feb 6, 2025
  154. Comment on: OpenAI O3-Miniilaksh, Hacker News commenter (self-described: Own API account on usage tier 5), Hacker News comment, published Jan 31, 2025

Jan 2025 to Oct 2026.

136 sources from practitioners, by month and sentiment.

The full readExplore all OpenAI API Signals7 praise themes, 9 concerns, 5 points of agreement and 3 disagreements across all three groups, with all 154 sources open to inspect.

Where It Fits

Where does OpenAI API belong in the stack?

Open Where It Fits: the Stack Field and the full map

OpenAI API is Core across Model and Build, supports Data and Operate, and touches Evaluate.

Business area
Product & Engineering
Function
Software Development
Operating stack
AI Application Platform
Primary role
Model API & Agent Platform
OpenAI API beside the rest of its stackThe Stack Field, every product on every layer
FootprintOpenAI API across the AI Application Platform stack. Bar height is its role on each layer.

  1. Model

    1. Model APIs: Core

      Model APIs, core. GPT-6 Astra, GPT-6.1 Sol, and GPT-6 Luna run through Responses and bill per token. Prompt caching lowers repeat input cost. Batch and Flex discount work that can wait.

    2. Model gateway: Touches

      Model gateway, touches. The API serves only OpenAI models. A gateway handles routing and failover across providers. Project spend and rate limits cover OpenAI traffic alone.

  2. Build

    1. Orchestration: Supports

      Orchestration, supports. The Agents SDK runs agent loops and handoffs in your Python or TypeScript application. The beta Agents API runs a managed Codex harness with sessions and compaction. Agent Builder shuts down on November 30, 2026. A framework such as LangGraph handles orchestration across providers.

    2. Tool use: Core

      Tool use, core. GPT-6 Astra and GPT-6.1 Sol require Responses for tool calling. The API supports function calling and Structured Outputs, plus remote MCP servers with approvals. Secure MCP Tunnel connects private servers. Hosted tools include web search, file search, and computer use.

  3. Data

    1. Retrieval: Supports

      Retrieval, supports. Embeddings models and file search over vector stores handle retrieval in the API. File search costs US$0.10 per GB per day after 1 GB and US$2.50 per 1,000 tool calls. Large document collections and hybrid search usually use a dedicated vector database.

  4. Evaluate

    1. Evaluation: Touches

      Evaluation, touches. OpenAI recommends task-specific evals. OpenAI set October 31, 2026 as the date its Evals platform becomes read-only for existing users and scheduled the shutdown for November 30, 2026. OpenAI points Evals users to Promptfoo as a migration path.

  5. Operate

    1. Observability: Supports

      Observability, supports. The Agents SDK and Agents API trace model calls, tool calls, and handoffs in the platform dashboard. The prompt caching dashboard reports hit rates. An observability tool traces other providers and application code.

    2. Cloud deployment: Supports

      Cloud deployment, supports. Scale Tier and Reserved Tier sell committed capacity. Regional processing keeps inference in the US or EU for a 10% uplift. GPT-6 models also run on Microsoft Azure and Amazon Bedrock under those clouds' accounts and quotas.

    3. Guardrails: Supports

      Guardrails, supports. OpenAI Moderation models detect harmful content in text and images. The moderation endpoint returns flags and scores that applications use to filter, route for review, or intervene.

Market mapThe layers OpenAI API covers, and who else owns each one.

  1. Model APIs

    CoreModel

  2. Tool use & integrations

    CoreBuild

  3. Orchestration & agent frameworks

    SupportsBuild

  4. Retrieval & grounding

    SupportsData

  5. Observability & tracing

    SupportsOperate

4 more layers on the full map. Core, Supports and Touches describe coverage. They say nothing about quality.

More on OpenAI API

  1. GILD ReviewGILD's evaluation, with the buying facts
  2. Research3 pieces
  3. Guides4 guides
  4. Operator Insights9 operator accounts
  5. Where It FitsOn the AI Application Platform stack
  6. Related Products6 products