Cracked AI Engineering

Grok 4 vs Grok 4 Fast None Reasoning

Grok 4 Fast None Reasoning offers 2.0M tokens context vs 256K tokens, Grok 4 Fast None Reasoning is more cost-effective, Grok 4 includes advanced reasoning. Compare full specs, pricing, and choose the best model for your use case.

Quick Overview

Grok 4

ZenMux

256K tokens context • $3.00 / $15.00 per 1M tokens

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Grok 4 Fast None Reasoning

ZenMux

2.0M tokens context • $0.20 / $0.50 per 1M tokens

View full specifications →

Detailed Comparison

Specification
Grok 4
Grok 4 Fast None Reasoning
Provider
ZenMux
ZenMux
Context Window
256K tokens
2.0M tokens
Max Output Tokens
256K tokens
30K tokens
Input Pricing (per 1M tokens)
$3.00
$0.20
Output Pricing (per 1M tokens)
$15.00
$0.50
Release Date
Jul 2025
Sep 2025

Capabilities

Capability
Grok 4
Grok 4 Fast None Reasoning
Text Generation
Vision
Function Calling
Advanced Reasoning
File Attachments

Which Model Should You Choose?

Choose Grok 4 if:

  • • You need advanced reasoning

Choose Grok 4 Fast None Reasoning if:

  • • You need a larger context window
  • • Cost efficiency is a priority