# OpenAI updates GPT-5.5 Instant behaviour in ChatGPT

> OpenAI updated ChatGPT's default model to GPT-5. 5 Instant on May 5, 2026, replacing GPT-5. 3 Instant for all users.

- **Source:** [Letsdatascience](https://letsdatascience.com/news/openai-updates-gpt-55-instant-behaviour-in-chatgpt-67c5e5c5?utm_source=gearopen.com&utm_medium=referral&utm_campaign=feed&utm_content=6a3d00281ad4c3e4640878a2)
- **Published:** 2026-06-25
- **Category:** AI & Bots
- **Tags:** #chatgpt #openai
- **Canonical:** http://localhost:4321/a/6a3d00281ad4c3e4640878a2

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_GearOpen's distilled summary. The full original article is published at Letsdatascience (source link above); GearOpen does not republish the source's full text._