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Grok 4 Fast vs Grok‑2

xAI Grok 4 Fast vs xAI Grok‑2 — side-by-side specs.

xAI
Grok 4 Fast
xAI
Grok‑2
Overview
CompanyxAIxAI
Release dateSep 2025Aug 14 2024
Model type
Open sourceNoNo
Specifications
Parameters
Context window
Benchmarks
Science reasoning
GPQA Diamond
Software engineering
SWE-Bench Verified
Multimodal understanding
MMMU
Timeline
Release gapGrok‑2 shipped 383 days before Grok 4 Fast

Which is better: Grok 4 Fast or Grok‑2?

Grok 4 Fast and Grok‑2 do not have directly comparable benchmark scores published on GPQA Diamond, SWE-Bench Verified, or MMMU. Grok‑2 shipped 383 days before Grok 4 Fast, so benchmark comparisons should account for the intervening progress.

Published specifications for these two models are limited — see each model page for the latest details.

Direct benchmark comparisons are unavailable — at least one of these models has not published scores on GPQA Diamond, SWE-Bench Verified, or MMMU.

Frequently asked questions

When was Grok 4 Fast released?
Grok 4 Fast was released by xAI on Sep 2025.
When was Grok‑2 released?
Grok‑2 was released by xAI on Aug 14 2024.

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