Improving health intelligence in ChatGPT

ChatGPT has improved its ability to help with health questions through a new model called GPT-5.5 Instant, which better recognizes when urgent care is needed, explains uncertainty honestly, and provides clearer information. The improvements were measured using physician-led evaluations (HealthBench, a set of tests that assess health response quality) and real-world usage data, showing a 71% reduction in factuality issues over two months. GPT-5.5 Instant is available free to all ChatGPT users and performs similarly to OpenAI's most advanced models on health-related tasks.