Back to Models
Grok 4.20 Beta
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.
3/12/2026
2,000,000 tokens
Specifications
Modalities
Input
text
image
Output
text
Supported Parameters
include_reasoning
logprobs
max_tokens
reasoning
response_format
seed
structured_outputs
temperature
tool_choice
tools
top_logprobs
top_p
Data policy
- Prompt retention
- Unknown — we could not confirm
- Training
- Unknown — not declared
"Unknown" does not mean "safe". It means we could not confirm it.
Whether a provider trains on prompts is a declared value from our terms with them. Retention is determined from the upstream listing for every host this model can reach. Neither is guessed.
Frequently asked questions
- Is Grok 4.20 Beta available on FastMetal?
- Not at the moment. Grok 4.6, from the same lab, is available on the FastMetal API today.
- What is the context window of Grok 4.20 Beta?
- 2,000,000 tokens, shared between the prompt and the response.