GPT-5.5 is here! Available in the API, Codex and ChatGPT today
OpenAI Developer Community
April 24, 2026
It is now available in the API!
x.com
OpenAI Developers
@OpenAIDevs
GPT-5.5 is now available in the API. The model brings higher intelligence and stronger token efficiency to complex work, helping tasks get done with fewer retries. x.com/16338749515087…
OpenAI Developers @OpenAIDevs
GPT-5.5 is here. It’s our smartest frontier model yet, introducing a new class of intelligence for agentic coding, computer use, knowledge work, and scientific research. Rolling out in ChatGPT and Codex today. API is coming soon. https://t.co/KS3Q0hB4bG
6:20 PM - 24 Apr 2026 400 31
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