Grok 4.20 Beta

grok Reasoning Tool Calling Attachments Structured Output

Grok 4.20 Beta is xAI's newest flagship model with industry-leading speed and agentic tool calling capabilities. It combines the lowest hallucination rate on the market with strict prompt adherance, delivering consistently precise and truthful responses. Reasoning can be enabled/disabled using the `reasoning` `enabled` parameter in the API. [Learn more in our docs](https://openrouter.ai/docs/use-cases/reasoning-tokens#controlling-reasoning-tokens)

Providers 2

Released Mar 12, 2026

Input Modalities text, image

Output Modalities text

Tarsk Use coding

Available Providers (2)

Provider	Model ID	Input Cost	Output Cost	Context	Max Output	Docs
OpenRouter	`x-ai/grok-4.20-beta`	$2.00/MTok	$6.00/MTok	2M	30K
Venice AI	`grok-4-20-beta`	$2.50/MTok	$7.50/MTok	2M	128K

Capabilities

Reasoning

Tool Calling

Attachments

Open Weights

Structured Output