OpenAI removes GPT-4o and GPT-4.1 models from its API on 14 January

OpenAI removes GPT-4o and GPT-4.1 models from its API on 14 January

14 October 2026: OpenAI will remove GPT-4o, GPT-4o mini, GPT-4.1 and GPT-4.1 mini from its API on 14 January 2027, along with every fine-tuned model built on them. It notified affected developers on 14 October and names gpt-6-luna as the recommended replacement for all four.

Not yet independently verified. Rests on OpenAI's own deprecations page; the entry does not say whether other GPT-4 aliases outside the listed snapshots are affected. We will update this when it can be confirmed, and remove this note.

Which model names stop working

Model	Snapshots removed	Replacement
GPT-4o	gpt-4o-2024-08-06, gpt-4o-2024-11-20	gpt-6-luna
GPT-4o mini	gpt-4o-mini-2024-07-18	gpt-6-luna
GPT-4.1	gpt-4.1-2025-04-14	gpt-6-luna
GPT-4.1 mini	gpt-4.1-mini-2025-04-14	gpt-6-luna

"Fine-tuned versions of these models follow the same shutdown schedule as their underlying base models," the page says. That is the part most likely to catch teams out: a custom model trained on GPT-4o mini for classification or extraction cannot simply be pointed at a new name, it has to be retrained or replaced, and its evaluation set rebuilt, before 14 January.

Why these four matter

GPT-4o and GPT-4.1, and their mini versions, became the default workhorses of many production integrations in 2024 and 2025: chat assistants, document extraction, routing and summarisation inside business software. Many products also call them indirectly, through frameworks, plugins or vendor features that hard-code a snapshot. Teams should search code, configuration and vendor documentation for the snapshot names above rather than rely on a search for "gpt-4o" alone, and ask software suppliers which model their AI features call.

A replacement chosen by the provider is not automatically equivalent. Output format, tool-calling behaviour, latency, token counts and price per call can all differ, so a migration needs a test run against real inputs, not just a string change.

The other retirements on OpenAI's calendar

The same page lists more dates in the coming months. The tts-1, tts-1-hd and two gpt-4o-mini-tts snapshots are removed on 6 January 2027, with gpt-realtime-2.1-mini as the replacement. whisper-1, gpt-4o-transcribe, gpt-4o-mini-transcribe and gpt-4o-transcribe-diarize go on 26 February 2027, in favour of gpt-live-transcribe or gpt-transcribe. And gpt-5.3-codex, gpt-5.1 and gpt-5.4-nano follow on 1 April 2027, which we covered with other AI API retirements in our earlier item. A team that runs voice, transcription and text features on OpenAI could face three migrations in under four months.

Sources

• OpenAI: Deprecations (entry of 14 October 2026, GPT-4 series model deprecations), 14 October 2026