OpenAI releases GPT-5.3 Instant for smoother everyday conversations and better search

OpenAI has released GPT-5.3 Instant, an update to the standard ChatGPT model. The new version aims to make everyday conversations feel more natural and useful. According to OpenAI, the model delivers more accurate answers, better web search results, and fewer unnecessary warnings and refusals. Hallucination rates drop by up to 26.8 percent for web searches and 19.7 percent for internal knowledge, depending on the scenario. The writing style also feels less robotic and preachy, OpenAI claims.

The system card shows some trade-offs on the safety front. GPT-5.3 Instant beats the older GPT-5.1 Instant on average when it comes to catching unauthorized content, but it actually performs worse than its direct predecessor, GPT-5.2 Instant. The model also takes a small hit on health-related queries (HealthBench) compared to the previous version.

GPT-5.3 Instant is rolling out now to all ChatGPT users and is available to developers via the API as "gpt-5.3-chat-latest." The outgoing GPT-5.2 Instant will stick around for paying users for another three months before OpenAI pulls the plug on June 3, 2026.