Grok 4.20
Grok 4.20 is a reasoning model from SpaceXAI with industry-leading speed and agentic tool calling capabilities.
Model by xAI
Install
Pick your client. Read the repository before you give any tool access to your data.
{
"model": "x-ai/grok-4.20",
"baseURL": "https://openrouter.ai/api/v1"
}OpenAI-compatible API: point any OpenAI SDK at the base URL and use this model id.
Settings it needs
OPENROUTER_API_KEYrequiredsecret
Get the weekly diff
The weekly diff: one email a week with new agent tools, notable updates and grade changes, plus security alerts for tools you follow. Double opt-in, one-click unsubscribe.
About
Use cases: model-inference
Reviews
Write a reviewNo reviews yet. Installed it? Reviews come from verified installers only. How reviews work
Price and limits
| Variant | Input $/M tokens | Output $/M tokens | Cached input $/M |
|---|---|---|---|
| Standard | $1.25 | $2.5 | $0.2 |
Price as of Oct 26, 2026 from OpenRouter · provider's own prices: docs.x.ai. Prices change often; check before you rely on one.
- Provider
- xAI
- Model id
x-ai/grok-4.20- Context window
- 2,000,000 tokens (2M)
- Max output
- 1,800,000 tokens
- Input
- text, image, file
- Output
- text
- Tool calling
- Yes
- Structured outputs
- Yes
- Reasoning
- Yes
- Weights
- Closed
- Released
- Mar 31, 2026
- Knowledge cutoff
- 2025-09-01
Details
- Auth
- API key
- License
- Proprietary
- Website
- x.ai
- First seen
- Oct 24, 2026
- Last checked
- Oct 26, 2026
- Source
- OpenRouter
More from xAI
- 0.592score
Grok 4.20 Multi-Agent
xAI
Grok 4.20 Multi-Agent is a variant of SpaceXAI’s Grok 4.20 designed for collaborative, agent-based workflows.
ModelAFreshness: A$1.25 / $2.52M ctx - 0.592score
Grok 4.3
xAI
Grok 4.3 is a reasoning model from SpaceXAI.
ModelAFreshness: A$1.25 / $2.51M ctx - 0.592score
Grok 4.6
xAI
Grok 4.6 is a model from SpaceXAI with frontier performance on coding, knowledge work, and STEM.
ModelAFreshness: A$2 / $6500K ctx - 0.592score
Grok 4.7
xAI
Grok 4.7 is SpaceXAI's flagship model for coding, agentic tasks, and knowledge work, succeeding Grok 4.6.
ModelAFreshness: A$2 / $6500K ctx - 0.592score
Grok Build 0.1
xAI
Grok Build 0.1 is SpaceXAI’s fast coding model trained specifically for agentic software engineering workflows.
ModelAFreshness: A$1 / $2256K ctx - 0.589score
Grok 4.5
xAI
Grok 4.5 is a model from SpaceXAI with frontier performance on coding, knowledge work, and STEM.
ModelAFreshness: A$2 / $6500K ctx
Cite this page
Grok 4.20: price, context window, tool use. Agent Mart. https://agentmart.dev/models/x-ai-grok-4-20 (last updated 2026-10-26)