Leaves ChatGPT and Codex on 14 October 2026, so from then on it's an API-only option at a fairly high $30 per million output tokens.

Kenning's take

What it does

GPT-5.5 is an OpenAI model for complex coding, computer use, research and knowledge work. It rolled out to ChatGPT Plus, Pro, Business and Enterprise users and to Codex in April 2026, with the API following a day later. OpenAI says it retires from ChatGPT and Codex on 14 October 2026, while staying in the API.

  • 1.05M-token context window
  • Built-in computer use, hosted shell and web search in the API
  • Text and image input
  • GPT-5.5 Pro variant for higher tiers
  • Structured outputs and function calling

Who it suits. Paid ChatGPT users and developers doing long coding and research tasks.

Key facts

Category
AI models
Part of
ChatGPT
Made by
OpenAI
Based in
United States
Released
23 April 2026
How to get it
ChatGPT Plus, Pro, Business and Enterprise and Codex until 14 October 2026; OpenAI API (model gpt-5.5) after that
Works on
ChatGPT (web, desktop, mobile), Codex, API
In the UK
Yes
API price
$5 per million input tokens, $30 per million output

Reviews and write-ups

FAQ

When was GPT-5.5 released?

It reached ChatGPT and Codex on 23 April 2026 and the API on 24 April 2026.

Is GPT-5.5 leaving ChatGPT?

Yes, OpenAI says it retires from ChatGPT and Codex on 14 October 2026 but remains in the API.

How much does GPT-5.5 cost in the API?

$5 per million input tokens and $30 per million output tokens.

Facts from the maker's own pages and the sources listed. Checked 2026-10-11.