| Category | Verified model names in the cited docs | What it means |
|---|---|---|
| ChatGPT reasoning | GPT-5.4 Thinking; GPT-5.4 / GPT-5.2 Thinking in plan docs | OpenAI describes GPT-5.4 Thinking as its most capable reasoning model in ChatGPT. Enterprise/Edu plan docs list a Thinking row with a long-term limit of 200 per week and a temporary increase above that level. |
| ChatGPT general use | GPT-5.3 / GPT-5.2 Instant | Enterprise/Edu model-limit docs list this Instant row with unlimited usage. |
| ChatGPT Pro | GPT-5.4 / GPT-5.2 Pro | Enterprise/Edu docs list this Pro row with 15 requests per month. A release note also says existing GPT-5.1 Pro conversations continue with GPT-5.4 Pro. |
| ChatGPT mini or fallback | GPT-5.4 mini | OpenAI says GPT-5.4 mini began rolling out in ChatGPT on March 18, 2026, with Free and Go access through the “Thinking” feature and fallback access for other users when rate limits apply. |
| API image, realtime voice, and speech | GPT Image 1.5 / gpt-image-1.5, gpt-image-1-mini, gpt-realtime-1.5, gpt-realtime-mini, gpt-4o-mini-tts | OpenAI’s API model docs list these as specialized models for image generation/editing, realtime speech-to-speech, and text-to-speech. |
| Codex | GPT-5.4, GPT-5.4-Mini, GPT-5.3-Codex, GPT-5.2-Codex, GPT-5.2, GPT-5.1-Codex-Max, GPT-5.1-Codex-mini | OpenAI’s Codex rate card lists these models and says code review uses GPT-5.3-Codex. |
| Retired from ChatGPT | GPT-4o, GPT-4.1, GPT-4.1 mini, OpenAI o4-mini, GPT-5 Instant/Thinking, GPT-5.1 Instant/Thinking/Pro | OpenAI retirement notices say these models were removed from ChatGPT in 2026, with API access treated separately. |
The highest-end ChatGPT model in the cited documentation is GPT-5.4 Thinking. OpenAI describes it as its most capable reasoning model in ChatGPT and says it is designed for difficult real-world work, including documents, images, tools, research, hard math, spreadsheets, frontend code, and slide creation.
For Enterprise and Edu plans, OpenAI’s model-limit page lists three main rows: GPT-5.3 / GPT-5.2 Instant with unlimited usage, GPT-5.4 / GPT-5.2 Thinking with a long-term limit of 200 per week, and GPT-5.4 / GPT-5.2 Pro with 15 requests per month. Because this is plan-limit documentation, it should not be read as a guarantee that every ChatGPT plan or workspace will show the same picker, naming, or usage limits.
GPT-5.4 mini is also documented for ChatGPT. OpenAI’s Enterprise and Edu release notes say it started rolling out on March 18, 2026; Free and Go users can access it through the “Thinking” feature in the plus menu, while other users may see it as a rate-limit fallback.
A model leaving ChatGPT does not automatically mean it has left the API. OpenAI’s pricing page says OpenAI APIs are billed separately from ChatGPT Plus, Business, Enterprise, and Edu subscriptions. OpenAI’s retirement announcement for GPT-4o, GPT-4.1, GPT-4.1 mini, and o4-mini also said there were no API changes at that time.
That distinction matters for developers, because the API catalog includes specialized models that are not simply the same as the ChatGPT model picker. In the cited API model docs, OpenAI lists image models, realtime speech-to-speech models, and a text-to-speech model.
| Developer use case | Models listed in the cited API docs | Source-backed note |
|---|---|---|
| Image generation and editing | GPT Image 1.5 / gpt-image-1.5, gpt-image-1-mini | OpenAI describes GPT Image 1.5 as a state-of-the-art image generation model and gpt-image-1-mini as a cost-efficient version of GPT Image 1. |
| Realtime voice | gpt-realtime-1.5, gpt-realtime-mini | OpenAI lists gpt-realtime-1.5 as its best voice model for audio input and output, and gpt-realtime-mini as a cost-efficient realtime model. |
| Text-to-speech | gpt-4o-mini-tts | OpenAI lists GPT-4o mini TTS for generating natural-sounding speech from text. |
| Codex work | GPT-5.4, GPT-5.4-Mini, GPT-5.3-Codex, GPT-5.2-Codex, GPT-5.2, GPT-5.1-Codex-Max, GPT-5.1-Codex-mini | OpenAI’s Codex rate card lists these models and says code review uses GPT-5.3-Codex. |
Several familiar OpenAI model names are no longer current ChatGPT choices in the cited OpenAI retirement notices.
| Date | Retired from ChatGPT | Important exception or API note |
|---|---|---|
| February 13, 2026 | GPT-4o, GPT-4.1, GPT-4.1 mini, OpenAI o4-mini, and GPT-5 Instant/Thinking | OpenAI’s retirement announcement said there were no API changes at that time. |
| March 11, 2026 | GPT-5.1 Instant, GPT-5.1 Thinking, and GPT-5.1 Pro | OpenAI says existing GPT-5.1 conversations continue with GPT-5.3 Instant, GPT-5.4 Thinking, or GPT-5.4 Pro, depending on the original model. |
| April 3, 2026 | GPT-4o exception window ended for Custom GPTs | OpenAI says ChatGPT Business, Enterprise, and Edu customers retained access to GPT-4o within Custom GPTs until April 3, 2026; after that, GPT-4o would be fully retired across all plans. |
Some older names still matter because they appear in announcements, API discussions, or retirement notices.
GPT-4.1 was introduced as an API family with GPT-4.1, GPT-4.1 mini, and GPT-4.1 nano. OpenAI described that family as improving coding and instruction following and supporting up to 1 million tokens of context. GPT-4.1 and GPT-4.1 mini were later retired from ChatGPT on February 13, 2026, according to OpenAI’s retirement notice.
o3 and o4-mini were introduced as o-series reasoning models trained to think longer before responding. OpenAI said that, in ChatGPT, these models could use tools such as web search, file analysis, Python, visual reasoning, and image generation. OpenAI later included o4-mini in the February 13, 2026 group retired from ChatGPT.
OpenAI also documents open models named gpt-oss-120b and gpt-oss-20b. One OpenAI page says gpt-oss-120b reaches near-parity with OpenAI o4-mini on core reasoning benchmarks while running efficiently on a single 80 GB GPU. Those sources establish the gpt-oss model names, but they should not be treated as a ChatGPT model-picker list or a complete API availability list.
gpt-image-1.5 and gpt-image-1-mini.gpt-realtime-1.5, gpt-realtime-mini, and gpt-4o-mini-tts.The most defensible shorthand is this: OpenAI’s cited 2026 ChatGPT documentation points to GPT-5.4 Thinking/Pro, GPT-5.3 Instant, GPT-5.4 mini, and GPT-5.2 variants in plan rows, while the API and Codex documentation separately list specialized image, realtime, speech, and coding models. GPT-4o, GPT-4.1, GPT-4.1 mini, o4-mini, GPT-5 Instant/Thinking, and GPT-5.1 variants should be treated as retired from ChatGPT rather than current ChatGPT model choices.
| Category | Verified model names in the cited docs | What it means |
|---|---|---|
| ChatGPT reasoning | GPT-5.4 Thinking; GPT-5.4 / GPT-5.2 Thinking in plan docs | OpenAI describes GPT-5.4 Thinking as its most capable reasoning model in ChatGPT. Enterprise/Edu plan docs list a Thinking row with a long-term limit of 200 per week and a temporary increase above that level. |
| ChatGPT general use | GPT-5.3 / GPT-5.2 Instant | Enterprise/Edu model-limit docs list this Instant row with unlimited usage. |
| ChatGPT Pro | GPT-5.4 / GPT-5.2 Pro | Enterprise/Edu docs list this Pro row with 15 requests per month. A release note also says existing GPT-5.1 Pro conversations continue with GPT-5.4 Pro. |
| ChatGPT mini or fallback | GPT-5.4 mini | OpenAI says GPT-5.4 mini began rolling out in ChatGPT on March 18, 2026, with Free and Go access through the “Thinking” feature and fallback access for other users when rate limits apply. |
| API image, realtime voice, and speech | GPT Image 1.5 / gpt-image-1.5, gpt-image-1-mini, gpt-realtime-1.5, gpt-realtime-mini, gpt-4o-mini-tts | OpenAI’s API model docs list these as specialized models for image generation/editing, realtime speech-to-speech, and text-to-speech. |
| Codex | GPT-5.4, GPT-5.4-Mini, GPT-5.3-Codex, GPT-5.2-Codex, GPT-5.2, GPT-5.1-Codex-Max, GPT-5.1-Codex-mini | OpenAI’s Codex rate card lists these models and says code review uses GPT-5.3-Codex. |
| Retired from ChatGPT | GPT-4o, GPT-4.1, GPT-4.1 mini, OpenAI o4-mini, GPT-5 Instant/Thinking, GPT-5.1 Instant/Thinking/Pro | OpenAI retirement notices say these models were removed from ChatGPT in 2026, with API access treated separately. |
The highest-end ChatGPT model in the cited documentation is GPT-5.4 Thinking. OpenAI describes it as its most capable reasoning model in ChatGPT and says it is designed for difficult real-world work, including documents, images, tools, research, hard math, spreadsheets, frontend code, and slide creation.
For Enterprise and Edu plans, OpenAI’s model-limit page lists three main rows: GPT-5.3 / GPT-5.2 Instant with unlimited usage, GPT-5.4 / GPT-5.2 Thinking with a long-term limit of 200 per week, and GPT-5.4 / GPT-5.2 Pro with 15 requests per month. Because this is plan-limit documentation, it should not be read as a guarantee that every ChatGPT plan or workspace will show the same picker, naming, or usage limits.
GPT-5.4 mini is also documented for ChatGPT. OpenAI’s Enterprise and Edu release notes say it started rolling out on March 18, 2026; Free and Go users can access it through the “Thinking” feature in the plus menu, while other users may see it as a rate-limit fallback.
A model leaving ChatGPT does not automatically mean it has left the API. OpenAI’s pricing page says OpenAI APIs are billed separately from ChatGPT Plus, Business, Enterprise, and Edu subscriptions. OpenAI’s retirement announcement for GPT-4o, GPT-4.1, GPT-4.1 mini, and o4-mini also said there were no API changes at that time.
That distinction matters for developers, because the API catalog includes specialized models that are not simply the same as the ChatGPT model picker. In the cited API model docs, OpenAI lists image models, realtime speech-to-speech models, and a text-to-speech model.
| Developer use case | Models listed in the cited API docs | Source-backed note |
|---|---|---|
| Image generation and editing | GPT Image 1.5 / gpt-image-1.5, gpt-image-1-mini | OpenAI describes GPT Image 1.5 as a state-of-the-art image generation model and gpt-image-1-mini as a cost-efficient version of GPT Image 1. |
| Realtime voice | gpt-realtime-1.5, gpt-realtime-mini | OpenAI lists gpt-realtime-1.5 as its best voice model for audio input and output, and gpt-realtime-mini as a cost-efficient realtime model. |
| Text-to-speech | gpt-4o-mini-tts | OpenAI lists GPT-4o mini TTS for generating natural-sounding speech from text. |
| Codex work | GPT-5.4, GPT-5.4-Mini, GPT-5.3-Codex, GPT-5.2-Codex, GPT-5.2, GPT-5.1-Codex-Max, GPT-5.1-Codex-mini | OpenAI’s Codex rate card lists these models and says code review uses GPT-5.3-Codex. |
Several familiar OpenAI model names are no longer current ChatGPT choices in the cited OpenAI retirement notices.
| Date | Retired from ChatGPT | Important exception or API note |
|---|---|---|
| February 13, 2026 | GPT-4o, GPT-4.1, GPT-4.1 mini, OpenAI o4-mini, and GPT-5 Instant/Thinking | OpenAI’s retirement announcement said there were no API changes at that time. |
| March 11, 2026 | GPT-5.1 Instant, GPT-5.1 Thinking, and GPT-5.1 Pro | OpenAI says existing GPT-5.1 conversations continue with GPT-5.3 Instant, GPT-5.4 Thinking, or GPT-5.4 Pro, depending on the original model. |
| April 3, 2026 | GPT-4o exception window ended for Custom GPTs | OpenAI says ChatGPT Business, Enterprise, and Edu customers retained access to GPT-4o within Custom GPTs until April 3, 2026; after that, GPT-4o would be fully retired across all plans. |
Some older names still matter because they appear in announcements, API discussions, or retirement notices.
GPT-4.1 was introduced as an API family with GPT-4.1, GPT-4.1 mini, and GPT-4.1 nano. OpenAI described that family as improving coding and instruction following and supporting up to 1 million tokens of context. GPT-4.1 and GPT-4.1 mini were later retired from ChatGPT on February 13, 2026, according to OpenAI’s retirement notice.
o3 and o4-mini were introduced as o-series reasoning models trained to think longer before responding. OpenAI said that, in ChatGPT, these models could use tools such as web search, file analysis, Python, visual reasoning, and image generation. OpenAI later included o4-mini in the February 13, 2026 group retired from ChatGPT.
OpenAI also documents open models named gpt-oss-120b and gpt-oss-20b. One OpenAI page says gpt-oss-120b reaches near-parity with OpenAI o4-mini on core reasoning benchmarks while running efficiently on a single 80 GB GPU. Those sources establish the gpt-oss model names, but they should not be treated as a ChatGPT model-picker list or a complete API availability list.
gpt-image-1.5 and gpt-image-1-mini.gpt-realtime-1.5, gpt-realtime-mini, and gpt-4o-mini-tts.The most defensible shorthand is this: OpenAI’s cited 2026 ChatGPT documentation points to GPT-5.4 Thinking/Pro, GPT-5.3 Instant, GPT-5.4 mini, and GPT-5.2 variants in plan rows, while the API and Codex documentation separately list specialized image, realtime, speech, and coding models. GPT-4o, GPT-4.1, GPT-4.1 mini, o4-mini, GPT-5 Instant/Thinking, and GPT-5.1 variants should be treated as retired from ChatGPT rather than current ChatGPT model choices.