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Grok 4 Fast Reasoning pricing

If you are budgeting for Grok 4 Fast Reasoning, start with the numbers below. We index 2 provider prices. Cheapest input is $0.200 per million tokens. Cheapest output is $0.500 per million tokens. The model lists a 131K context window in our data.

131K context·2 providers·verified Apr 7, 2026
Best input$0.200per 1M tokens · Xai
Best output$0.500per 1M tokens · Xai

Pricing across providers

All figures are list prices per million tokens unless a column says otherwise. 2 offers are listed for Grok 4 Fast Reasoning. Best input in this view: Xai.

X
Xainative
Input / 1M
$0.200
Output / 1M
$0.500
Cached in: $0.050
A
Azure
Input / 1M
$0.200
Output / 1M
$0.500

Input vs output · per provider

Cost calculator

Pick any of the providers above and type how many tokens you expect per day, week, or year. We turn that into rough dollar totals for Grok 4 Fast Reasoning.

Provider

In: $0.200/M·Out: $0.500/M·Cache: $0.050/M

0.020000¢ / req

0.025000¢ / req

Daily
$4.50
Monthly
$135
Annual
$1.6K

Model specifications

Context length, caps, and capability flags for Grok 4 Fast Reasoning. Values follow the main provider (Xai) record in our index.

Context window
131,072 tokens
Max output
131,072 tokens
Vision (images)
No
Tool / function calling
Yes
Streaming
No
Released
N/A
Primary provider
Xai
Model family
N/A

Compare Grok 4 Fast Reasoning

These links open full side by side pages for Grok 4 Fast Reasoning. We picked pairs that people often shop together. 6 ready to open.

Frequently asked questions

Read these after the table if you want plain language around Grok 4 Fast Reasoning rates.

Grok 4 Fast Reasoning costs $0.20 per million input tokens and $0.50 per million output tokens via the native API. Prompt caching reduces input costs to $0.05/M tokens.

Also from Xai

Other models by Xai with live pricing in our catalog.