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Pyyan / Compare / Grok 4.20 Reasoning vs Claude Sonnet 5

Grok 4.20 Reasoning vs Claude Sonnet 5

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Language Models · verified 13 Aug 2026

Grok 4.20 ReasoningxAIcurrent
Claude Sonnet 5Anthropiccurrent
3 slots left
SpecificationGrok 4.20 ReasoningClaude Sonnet 5
SummaryAgentic reasoning SKU.Near-Opus quality on coding and agentic work at Sonnet cost.
Context1M1M
Input ($/Mtok)$1.25$3
Output ($/Mtok)$2.5$15
LicenceProprietaryProprietary
Max output—128K
Model IDgrok-4.20-0309-reasoningclaude-sonnet-5
CategoryLanguage ModelsLanguage Models
OfficialxAI ↗Anthropic ↗

Highlighted rows are where these differ.

Grok 4.20 Reasoning

Agentic reasoning SKU.

Best for multi-step agents.

Full spec sheet →

Claude Sonnet 5

  • Adaptive thinking on by default
  • New tokenizer — roughly 30% more tokens for the same text
  • Introductory $2/$10 through 31 Aug 2026

Best for high-volume production.

Full spec sheet →