Models
OpenAI retired the o3 model family from ChatGPT on 26 August 2026. The move closes a ninety-day sunset window and pushes remaining reasoning-model users toward GPT-5.6 or the pricier o3-pro tier.
OpenAI first flagged the retirement in a ChatGPT release note dated 28 May 2026, giving o3 a ninety-day sunset period that expired today. The change is ChatGPT-only, the…
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