Chat with GPT-OSS 120B.

OpenAI’s open-weight model. Only 5B of its 117B works on each word, so it answers fast, and it is built to reason step by step.

Start chatting with GPT-OSS 120B now — free, no account

At a glance

  • Maker: OpenAI
  • Active parameters: 117B
  • Context window: 128k
  • Size: Large
  • Memory: Handles long documents
  • Good at: Reasoning and agent work
  • Supports: tools, zero data retention

Announced in Introducing gpt-oss.

Model availability changes as upstream capacity comes and goes — the picker on the chat page shows what is ready right now.

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