Grok 4 Fast API Cost Calculator
Estimate your monthly API costs for Grok 4 Fast from X Ai.
Pricing per 1M tokens
Pricing last verified: Mar 21, 2026
30-Day Price History
Solid line: input price · Dashed line: output price
Estimate Your Costs
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Cost Breakdown
Compare with Similar Models
| Model | Input/1M | Output/1M |
|---|---|---|
| Grok 4.1 Fast X Ai | $0.2000 | $0.5000 |
| Grok 3 Mini X Ai | $0.3000 | $0.5000 |
| Grok 3 Mini Beta X Ai | $0.3000 | $0.5000 |
| Grok Code Fast 1 X Ai | $0.2000 | $1.50 |
| Grok 4.20 Beta X Ai | $2.00 | $6.00 |
Frequently Asked Questions
How much does Grok 4 Fast cost per token?
Grok 4 Fast is priced at $0.2000 per 1M input tokens and $0.5000 per 1M output tokens. Use the calculator above to estimate your monthly costs based on your usage volume.
What is the context window for Grok 4 Fast?
Grok 4 Fast has a context window of 2M tokens (2,000,000 tokens). The maximum output length is 30K tokens.
Does Grok 4 Fast support image inputs (vision)?
Yes, Grok 4 Fast supports vision/image inputs. You can send images as part of your prompts.
Does Grok 4 Fast support function calling (tool use)?
Yes, Grok 4 Fast supports function calling (also called tool use). You can define custom functions that the model can invoke as part of its responses.
How does Grok 4 Fast compare to similar models?
Grok 4 Fast costs $0.2000 input and $0.5000 output per 1M tokens. Grok 4 Fast is competitively priced compared to Grok 4.1 Fast ($0.2000 input / $0.5000 output per 1M tokens). See the "Compare with Similar Models" table above, or visit the Grok 4.1 Fast page at /tools/cost-calculator/x-ai/grok-4-1-fast.