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Grok 4.20 Reasoning – Model Docs — Person.run

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Grok 4.20 Reasoning

Grok 4.20 Beta is the newest flagship model from xAI with industry-leading speed and agentic tool calling capabilities. It combines the lowest hallucination rate on the market with strict prompt adherence, delivering consistently precise and truthful responses.

Model overview

Model ID: spacexai/grok-4.20-reasoning
Provider: spacexai
Type: language
Context window: 2,000,000 tokens
Max output tokens: 2,000,000

Tags: reasoning, tool-use, implicit-caching, vision, file-input, web-search

Model pricing

Metric	Value
`Input tokens (/1M)`	`$1.25`
`Output tokens (/1M)`	`$2.50`
`Image generation`	`n/a`
`Cached input read (/1M)`	`$0.20`
`Cached input write (/1M)`	`n/a`
`Pricing source`	`gateway`

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