xAI: Grok 4.20 (0309) Reasoning

xai/grok-4.20-0309-reasoning

xAI Grok 4.20 (0309) Reasoning API pricing

Grok 4.20 (0309) Reasoning costs $0.500 per million input tokens and $1.00 per million output tokens on Oxyy. These are the pay-as-you-go prices after the current 60% discount (Launch Promo; standard price $1.25 input and $2.50 output), and cached input tokens are billed at $0.080 per million. It accepts text and images and returns text, with a 1M-token context window. A cheaper xAI option is Grok Build 0.1 at $0.400 / $0.800 per 1M tokens; for every model and rate, see Grok API pricing.

Pinned 0309 release of Grok 4.20 in reasoning mode, with a 1M token context window.
ModalitiesTextImageText
Price$0.500 / $1.00 per 1M tokens in / outAll Grok API pricing
Context1M

Providers

Where this model runs, and what each route costs. Requests are sent to a healthy provider automatically; if one errors, the gateway retries against another serving the same model.

ProviderInput /MOutput /MCache read /M
xAI$0.500$1.00$0.080

Capabilities (12)

StreamingTool callingStructured outputReasoningSystem promptVisionPrompt cachingWeb searchX SearchCode executionPriority ProcessingBatch

Supported parameters (2)

toolsresponse_format

A parameter not listed here may be removed before the request reaches the model. When it is, the request still succeeds and the response names it, with the reason, in provider_specific_fields.dropped_params.

Pricing

What this model costs on Oxyy, pay as you go. "Charged" is the rate a request is billed at; the standard price is shown beside it for reference.

Input price
$0.500
per 1M input tokens · standard price $1.25
Output price
$1.00
per 1M output tokens · standard price $2.50
RateStandard priceChargedUnit
Input$1.25$0.500per 1M input tokens
Output$2.50$1.00per 1M output tokens
Cached input$0.200$0.080per 1M cached input tokens

Discount. Charged rates include the current "Launch Promo" discount of 60% on every rate.

Long-context pricing. Once the prompt is larger than the threshold, the whole request is billed at these charged rates per 1M tokens; rates not listed keep the price above.From 200,000 tokens in the prompt: input $1.00 / output $2.00 / cache read $0.160.

UTC

Specifications

Model ID
grok-4.20-0309-reasoning
Developer
xAI
Type
Text
Input
Text and images
Output
Text
Context window
1,000,000 tokens
Tokenizer
Grok
Series
Grok 4.20
Image input
Up to 20 MB each
Endpoint
/v1/chat/completions

Best for

ReasoningLong contextPinned snapshot

Quickstart

Call grok-4.20-0309-reasoning with a POST to /v1/chat/completions on https://api.oxyy.ai, using your Oxyy API key from the OXYY_API_KEY environment variable. The same key works for every model in the catalog.

import os
from openai import OpenAI

client = OpenAI(
    base_url="https://api.oxyy.ai/v1",
    api_key=os.environ["OXYY_API_KEY"],
)

response = client.chat.completions.create(
    model="grok-4.20-0309-reasoning",
    messages=[
        {"role": "user", "content": "Explain unified AI APIs in one sentence."},
    ],
)
print(response.choices[0].message.content)

Availability

The share of requests to this model that completed successfully over the last 30 days. Requests the caller cancelled, and requests still in flight, are not counted. When an upstream provider errors, the gateway retries against another provider serving the same model, so a single provider incident does not necessarily show up here.

Requests (30 days)
54
A success rate is shown from 100 completed requests
Days with traffic
4
of the last 30 days

Frequently asked questions

What is Grok 4.20 (0309) Reasoning?
Pinned 0309 release of Grok 4.20 in reasoning mode, with a 1M token context window.
How much does Grok 4.20 (0309) Reasoning cost?
Grok 4.20 (0309) Reasoning costs $0.500 per million input tokens and $1.00 per million output tokens on Oxyy. These are the pay-as-you-go prices after the current 60% discount (Launch Promo; standard price $1.25 input and $2.50 output), and cached input tokens are billed at $0.080 per million. You pay per request, with no subscription.
What is the context length of Grok 4.20 (0309) Reasoning?
Grok 4.20 (0309) Reasoning has a context window of 1,000,000 tokens.
Does Grok 4.20 (0309) Reasoning support tool calling and structured outputs?
Yes — Grok 4.20 (0309) Reasoning supports both tool calling and structured outputs.
What inputs and outputs does Grok 4.20 (0309) Reasoning support?
Grok 4.20 (0309) Reasoning accepts text and images as input and returns text.
Which API endpoint does Grok 4.20 (0309) Reasoning use?
Send a POST request to https://api.oxyy.ai/v1/chat/completions with "model": "grok-4.20-0309-reasoning", authenticated with your Oxyy API key. It is also served on /v1/responses (Responses API).
What other models does xAI have?
xAI also offers Grok 4.20 (0309) Non-Reasoning, Grok 4.20 (0309) Multi-Agent, Grok 4.3 and Grok 4.5 through Oxyy.

Alternatives to Grok 4.20 (0309) Reasoning

Models of the same kind from other vendors, closest in price first. Prices are pay-as-you-go on Oxyy, through the same API key.

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