GPT-5.3 Instant
GPT-5.3 Instant updates ChatGPT's default fast model with fewer needless refusals and caveats and better-grounded web answers.
Aimed at tone, relevance and conversational flow rather than benchmark gains; also exposed in the API as gpt-5.3-chat-latest. It replaced earlier defaults until GPT-5.5 Instant (2026-05-05).
- Date
- Tuesday, 3 March 2026
- Lab
- OpenAI
- Kind
- model
- Access
- closed API
Sources
- openai.com/index/gpt-5-3-instant/
- deploymentsafety.openai.com/gpt-5-3-instant/
- developers.openai.com/api/docs/changelog
This record was checked against its sources on 6 October 2026. How we check