Grok 4.20 Reasoning
This dated Grok 4.20 endpoint is the reasoning member of the release. It accepts text and images and returns text.
What the release provides
The model card lists a one-million-token context, function calls, structured outputs and batch access. The generic grok-4.20 name is among its aliases.Grok 4.20 Reasoning API model card
How to use it well
Practical guidance. Choose this endpoint when a workflow benefits from intermediate problem solving. Compare it with the separate non-reasoning release on the same questions. Evaluate answer accuracy and elapsed response time rather than assuming that a longer reasoning process improves every task.
Specifications & access
| Detail | Value and conditions |
|---|---|
| Access | API |
| Model identifiers | grok-4.20-0309-reasoning |
| Context window | 1,000,000 tokens Published API context limit Grok 4.20 Reasoning API model card |
| Input price | 1.25 USD per million tokens Standard uncached input; prompt below 200,000 tokens; higher rate applies to all tokens at the threshold Grok 4.20 Reasoning API model card |
| Output price | 2.5 USD per million tokens Standard output; prompt below 200,000 tokens; excludes tools and batch discounts Grok 4.20 Reasoning API model card |