Grok 4.20 Reasoning

xAI · March 2026

An earlier Grok that thinks before answering, so it is slower.

Best for
Deep reasoning
Superseded by
Grok 4.3
  • Context window

    1,000,000 tokens

    ≈ 750,000 words · about 3,000 pages

Modalities

  • TextInput and output
  • ImageInput only
  • AudioNot supported
  • VideoNot supported

Features

  • StreamingSupported
  • Function callingSupported
  • Structured outputsSupported
  • Fine-tuningNot supported

Tools

  • Web searchSupported
  • Image generationSupported
  • Code interpreterSupported
  • Hosted shellSupported
  • Apply patchNot supported
  • SkillsNot supported
  • Computer useNot supported
  • Tool searchNot supported

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