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⚡ EfficientVery Cheap

Grok 4.1 Fast

by xAI

Fast and affordable reasoning model with 2M context window

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Input Price

$0.2

per 1M tokens

Output Price

$0.5

per 1M tokens

Context Window

2,000K

tokens (131.072K max output)

Specifications

Release Date2026-01-15
Category⚡ Efficient
Context Window2,000,000 tokens
Max Output131,072 tokens
ProviderxAI
Input Cost$0.2 / 1M tokens
Output Cost$0.5 / 1M tokens
Price TierVery Cheap

Capabilities

textreasoningcode

Related Use Cases

Monthly Cost Estimates

Usage LevelDaily TokensDailyMonthlyYearly
Light~50 requests/day100K in / 20K out$0.03$0.90$11
Medium~200 requests/day500K in / 100K out$0.15$4.50$55
Heavy~1K requests/day2,000K in / 500K out$0.65$19.50$237
Enterprise~5K requests/day10,000K in / 2,000K out$3.00$90.00$1095

Cost Calculator

Alternatives to Grok 4.1 Fast

Frequently Asked Questions

How much does Grok 4.1 Fast API cost per million tokens?
Grok 4.1 Fast costs $0.2 per million input tokens and $0.5 per million output tokens as of 2026. These are the standard API rates from xAI.
What is the Grok 4.1 Fast context window?
Grok 4.1 Fast supports a 2M context window (2,000,000 tokens), which means you can process up to 2M tokens in a single API call.
How much does Grok 4.1 Fast cost per month?
At medium usage (~200 requests/day with 500K input and 100K output tokens/day), Grok 4.1 Fast costs approximately $4.50/month. Light usage runs about $0.90/month, and heavy usage (~1K requests/day) around $19.50/month.
Is there a cheaper alternative to Grok 4.1 Fast?
Yes — Gemini 2.5 Flash-Lite by Google is a cheaper option at $0.1/M input tokens vs $0.2/M for Grok 4.1 Fast. Other budget alternatives include models in the efficient tier.
Is Grok 4.1 Fast good for ai agent / agentic workflows?
Grok 4.1 Fast is a efficient model with support for text, reasoning, code. For ai agent / agentic workflows, it offers 2M context and costs $0.2/M input tokens — a budget-friendly choice for this use case.

Grok 4.1 Fast Comparisons

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