GPT-5.5 Released: Everything You Need to Know
Update, July 10, 2026: GPT-5.5 has since been succeeded by GPT-5.6, which reached general availability on July 9, 2026 with the Sol, Terra, and Luna tiers and is now OpenAI’s frontier model. This guide remains the deep reference on GPT-5.5, which stays available as the fast Instant default across ChatGPT tiers. On April 23, 2026, […]
