# gpt-4.1-nano

Calls to the model gpt-4.1-nano on OpenAI stopped working on October 23, 2026.

On October 23, 2026, the model gpt-4.1-nano was shut down. Calls specifying model gpt-4.1-nano fail since that day. This retirement also covers the gpt-4.1-nano-2025-04-14 snapshot.

## The error OpenAI returns once gpt-4.1-nano is gone

HTTP 404

```json
{"error":{"message":"The model `gpt-4.1-nano` has been deprecated, learn more here: https://platform.openai.com/docs/deprecations","type":"invalid_request_error","param":null,"code":"model_not_found"}}
```

## What to use instead

Move to gpt-5.6-luna, which is the substitute model recommended by OpenAI.

- API: OpenAI (api.openai.com)
- Model: gpt-4.1-nano
- Released: April 14, 2025 (models.dev)
- Kind: Model retirement
- Takes effect: October 23, 2026
- Calls after that day: fail
- Calls it hits: `model gpt-4.1-nano`
- Source: [Deprecations page](https://developers.openai.com/api/docs/deprecations)
- Verified: November 6, 2026, against OpenAI's own pages
- Page: https://www.okapi.bot/models/openai/gpt-4.1-nano/

## OpenAI's words

> Shutdown date: October 23, 2026; Model snapshot: gpt-4.1-nano | gpt-4.1-nano-2025-04-14; Substitute model: gpt-5.6-luna

Okapi finds the calls this change hits in your repo and opens the pull request with the fix: https://github.com/apps/okapi-agent