Research note
Research note: OpenAI will remove GPT-4o and GPT-4.1 from its API on 14 January 2027 and points developers to GPT-6 Luna
How we checked which GPT-4-series versions OpenAI is removing from its API, the date, and the replacement it recommends.
What we set out to check
Which model versions OpenAI is removing from the API, when, what it recommends instead, and what the replacement costs.
What we found
- OpenAI’s deprecations page has a 14 October 2026 entry listing five model versions across four models, all removed on 14 January 2027, with gpt-6-luna as the replacement.
- Fine-tuned models follow their base model’s date.
- The pricing page lists gpt-6-luna at $0.10, $0.01 cached and $0.50 per million tokens on the standard tier.
Numbers that differ
One summary site described a related alert as being about image models. The deprecations page itself is about GPT-4-series chat models, so we rely on the page.
Labels we chose and why
- Confirmed for all facts, which come from OpenAI’s own pages.
What we could not verify
- How many developers still use these models.
- When the gpt-6-luna price took effect; the pricing page does not say.
What we searched
- OpenAI deprecations GPT-4o January 14 2027
- gpt-6-luna pricing
- OpenAI retiring GPT-4o ChatGPT February 2026
Every source we read
| Source | Used? | Why |
|---|---|---|
| OpenAI API: Deprecations | USED | Primary source for the model list, the date and the replacement. |
| OpenAI API: Pricing | USED | Price of gpt-6-luna. |
| Shelly Palmer | USED | Independent write-up matching the date and replacement, with migration advice. |
| OpenAI: Retiring GPT-4o and older models | USED | January 2026 post on the ChatGPT retirement. |
| AI Weekly | NOT USED | Older article about image models; its headline did not match this notice. |