#gpt-5

OpenAI announced GPT-5 on 2025-08-07 for both ChatGPT and API usage. The launch highlights include a reported 45% hallucination reduction vs GPT-4o and major benchmark gains such as HealthBench Hard 44.6.

OpenAI said on January 29, 2026 that ChatGPT would stop offering GPT-4o and older model options from February 13, 2026. GPT-4o, GPT-4.5, and o4-mini are being replaced by GPT-5, GPT-5 thinking, and o5-mini respectively.

OpenAI launches GPT-5.3-Codex, the first model to debug its own training and manage deployment. Released with tight security controls due to cybersecurity concerns.

A new study shows OpenAI's GPT-5 model outperformed federal judges in complex legal reasoning tasks.