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Grok 4.20 0309 Reasoning

xai/grok-4.20-0309-reasoning

Reasoning variant of the Grok 4.20 0309 snapshot, which the plain grok-4.20 alias resolves to, with a 1M-token context, tool calling and structured outputs. A previous-generation model, superseded by Grok 4.3 and now by Grok 4.7.

Get API KeyRead the Docs
API
curl "$AUDIOLAB_API_URL/v1/responses" \
  -H "Authorization: Bearer $AUDIOLAB_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
  "model": "xai/grok-4.20-0309-reasoning",
  "input": "Help me plan my next project.",
  "max_output_tokens": 256,
  "store": false
}'
Read docs
Input Price
$1.0625 / 1M tokens
Output Price
$2.125 / 1M tokens
Context
1M tokens
Output Cap
128K tokens

Capabilities

Explore what Grok 4.20 0309 Reasoning supports, then use the API section for a request tailored to this model.

Max tokensToolsTool choiceParallel tool callsStructured outputs

Model Information

Provider
xAI
Product
Language Models
Release Date
Mar 2026
Data Policy
No training
Region
Global
Input
Text
Output
Text
Provider Documentation

Playground

Try Grok 4.20 0309 Reasoning by xAI. Requests use the selected workspace’s credits and API pricing.

Grok 4.20 0309 ReasoningCredits —
Grok 4.20 0309 Reasoning
This model uses a dedicated input format. Explore its API example or open the supported playground.
View API reference
Sign in to run a requestAPI reference

Providers

Compare available endpoints, pricing, and context limits for Grok 4.20 0309 Reasoning.

ProviderContextOutput CapInput PriceOutput PriceEndpoint
xAI1M tokens128K tokens$1.0625 / 1M tokens$2.125 / 1M tokens
grok-4.20-0309-reasoning

Prices are catalog rates. Your workspace’s estimate and endpoint pricing determine the final charge.

Input and Output Limits

Formats and limits AudioLab enforces on each request.

LimitValue
Max input tokens1000000
Max output tokens128000

Provider Notes

General LLM inference is an integration preview. Managed billing and deployment acceptance must be enabled before requests can be served.

Performance

Status

Current catalog availability. Your workspace’s access is checked separately before a request runs.

Getting Started

Use your workspace API key and the exact model identifier below. Set the API URL to the endpoint shown in your workspace and keep credentials on your server.

API
curl "$AUDIOLAB_API_URL/v1/responses" \
  -H "Authorization: Bearer $AUDIOLAB_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
  "model": "xai/grok-4.20-0309-reasoning",
  "input": "Help me plan my next project.",
  "max_output_tokens": 256,
  "store": false
}'
Read docs
Read the Endpoint Reference

Request Parameters

Available parameters depend on the provider and request format. The endpoint reference explains accepted values and required fields.

ParameterDetails
modelxai/grok-4.20-0309-reasoning — Required model identifier.
max_tokensView Accepted Values
toolsView Accepted Values
tool_choiceView Accepted Values
parallel_tool_callsView Accepted Values
structured_outputsView Accepted Values

Input and Output Limits

Formats and limits AudioLab enforces on each request.

LimitValue
Max input tokens1000000
Max output tokens128000

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Grok 4.5xAI500K tokens$1.70 / 1M tokens$5.10 / 1M tokens
Grok Build 0.1xAI256K tokens$0.85 / 1M tokens$1.70 / 1M tokens
Grok 4.3xAI1M tokens$1.0625 / 1M tokens$2.125 / 1M tokens
Grok 4.20 0309 Non-ReasoningxAI1M tokens$1.0625 / 1M tokens$2.125 / 1M tokens
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