← Artificial Acceleration
OpenAI · GPT series

GPT-5.5

Released 23 Apr 2026 · 37 days after GPT-5.4 nano
notable release

Flagship; API a day later.

Intelligence
—
no index score yet
Price
$11.25
per 1M tokens, 3:1 in/out · $5 in / $30 out
Speed
—
not measured
Weights
Closed
US lab

OpenAI’s best score over time

9 Jul 202626 Oct 2026
← previous from OpenAIGPT-5.4 nano