Tech & Science
AI models
OpenAI ships GPT-5.5 Instant as the new ChatGPT default
OpenAI replaced GPT-5.3 Instant with GPT-5.5 Instant as the default ChatGPT model on 5 May 2026. The company says the upgrade cuts hallucination rates in legal, medical and financial queries by roughly half while keeping per-token latency at sub-300 milliseconds.