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OpenAI launches GPT-5

★★★★★model-releaseOpenAIconfidence: high

GPT-5 unified OpenAI's fast and reasoning models into one system with a real-time router, becoming the default ChatGPT model for all users with state-of-the-art results in coding, math and health, and reduced hallucinations.

Key facts

What happened

After over two years of anticipation, OpenAI shipped GPT-5; reception mixed praise for capability with complaints over the removal of older models, which were partly restored.

Why it matters

Brought reasoning-model capability to hundreds of millions of free users by default.

Changelog

  • 2026-09-29: created

Related events

  1. OpenAI releases GPT-4 ★★★★★
  2. OpenAI announces o3, scoring 75.7–87.5% on ARC-AGI ★★★★★
  3. OpenAI releases GPT-5.2 ★★★
  4. GPT-5 Pro proves an improved convex-optimisation bound, which humans had already surpassed ★★

Sources (2)

id: 2025-08-07-gpt-5 · updated 2026-09-29 · open in the interactive timeline