ChatGPT — May 28, 2026

Changed

• GPT-5.5 Instant Update
• We’re updating GPT-5.5 Instant in ChatGPT and the API to improve response style and quality. It’s now easier to read, more natural in everyday conversations, and better paced in practical help tasks, with fewer overly long or bullet-heavy responses. With this update, canvas will no longer be available in GPT-5.5 Instant or GPT-5.5 Thinking. Writing and coding functionality is now supported directly in chat responses through writing blocks and code blocks. Paid users can continue using canvas for a limited time through legacy models until those models are sunset.
• Retiring OpenAI o3 and GPT-4.5
• Today, we’re continuing to retire older models with limited usage in ChatGPT so we can better serve our newer, most capable models. OpenAI o3 will be retired from ChatGPT on August 26, 2026 following a 90-day sunset period, and GPT-4.5 will be retired from ChatGPT on June 26, 2026 following a 30-day sunset period. These models are currently available to paid users only via model settings. These changes apply to ChatGPT only; there are no changes to the API.