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GPT-4.5 vs Grok Code Fast 1

OpenAI GPT-4.5 vs xAI Grok Code Fast 1 — side-by-side specs.

OpenAI
GPT-4.5
xAI
Grok Code Fast 1
Overview
CompanyOpenAIxAI
Release dateFeb 27 2025Aug 28 2025
Model type
Open sourceNoNo
Specifications
Parameters
Context window
Benchmarks
Science reasoning
GPQA Diamond
Software engineering
SWE-Bench Verified
Multimodal understanding
MMMU
Timeline
Release gapGPT-4.5 shipped 182 days before Grok Code Fast 1

Which is better: GPT-4.5 or Grok Code Fast 1?

GPT-4.5 and Grok Code Fast 1 do not have directly comparable benchmark scores published on GPQA Diamond, SWE-Bench Verified, or MMMU. GPT-4.5 shipped 182 days before Grok Code Fast 1, 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 GPT-4.5 released?
GPT-4.5 was released by OpenAI on Feb 27 2025.
When was Grok Code Fast 1 released?
Grok Code Fast 1 was released by xAI on Aug 28 2025.

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