OpenAI to End Legacy Model APIs on October 23, Check Model IDs in Use First

OpenAI’s official Deprecations document states that the API shutdown date for several legacy models is October 23, 2026. The affected models include GPT-4-series snapshots, GPT-3.5 Turbo, o1, o3-mini, and o4-mini. After the shutdown date, requests calling these model IDs will fail. With four days remaining until the shutdown, it is safer to check the model IDs in your code and settings now.

1. Find the model IDs being discontinued first

According to the official table, the items being discontinued on October 23 are gpt-4-0613, gpt-4-turbo, gpt-4-1106-preview, gpt-3.5-turbo-0125, gpt-4o-2024-05-13, gpt-4.1-nano, o1, o1-pro, o3-mini, o4-mini, and gpt-image-1. Also check cases where the same names are used as aliases. For example, if you are using gpt-4-turbo or o4-mini with a fixed model ID, they are also subject to discontinuation on the same day.

2. Check the recommended replacement models

Most of the replacement models suggested by OpenAI are gpt-5.6-sol, gpt-5.6-terra, and gpt-5.6-luna. The guidance is to move GPT-4-series models, o1, and o3-mini to gpt-5.6-sol; o4-mini and gpt-3.5-turbo to gpt-5.6-terra; and gpt-4.1-nano to gpt-5.6-luna. gpt-image-1 can be moved to gpt-image-2.5-sunburst or gpt-image-2.5-flare. The replacement models are only OpenAI’s recommendations, so test response formats, tool calls, and costs with actual requests before switching.

3. Check fine-tuned models separately

Fine-tuned models will also be discontinued on the same day. The list includes ft-gpt-3.5-turbo, ft-gpt-4, ft-gpt-4.1-nano-2025-04-14, ft-babbage-002, ft-davinci-002, and ft-o4-mini-2025-04-16. Fine-tuned models do not migrate automatically when the base model is changed, so you must either retrain with the new base model or compare the results using evaluation data.

4. Mark the next shutdown date as well

October 23 is not the end. The same document also lists GPT-4o and GPT-4.1-series models, including gpt-4o-2024-08-06 and gpt-4.1-2025-04-14, that will be discontinued on January 14, 2027. This date was announced separately on October 14. Do not check the model list just once and stop; periodically check the official documentation or the shutdown_date field in the model list API.

Related article: Three models to be removed from GitHub Copilot on November 16; check fixed model settings first ↗

Source: OpenAI API Deprecations ↗

This English edition was written and translated with AI assistance, with sources provided. For errors or additional information, please request a correction. Editorial policy