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GPT-5 vs Grok 4.1 Fast

Head to head on 20 shared benchmarks, with price, context window, and release dates.

Benchmark scores

74

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Model
GPT-5

OpenAI

48.3%61.1%1623elo72.868.6%6.6%45.0%83.4%54.3%49.6%83.7%82.0%65.5%18.0%43.7%37.8%73.4%12.9%20.1%0.0%46.7%-91.1%88.0%94.6%0.0%0.150.0%68.1%4.5857.7%80.0%80.0%91.7%32.4%0.0%88.9%83.3%100.0%-48.9%-58.2%-------37.5%0.521.62100.0%86.1%-0.0%92.7%92.7%-93.3%10.0%0.0%60.0%0.260.0%74.9%74.4%2.3487.5%0.8654.8%90.0%90.0%56.7%
Grok 4.1 Fast

xAI

34.3%66.0%1324elo40.163.7%5.1%36.5%80.2%39.9%28.1%78.7%74.3%42.6%4.0%31.3%29.6%73.1%14.4%1.2%63.7%-62.0%-----------------11.8-35.0%-64.7%69.6%52.2%28.2%74.3%83.7%80.2%-----60.8%---100.0%--------------51.0%
2 / 2 models
AttributeGPT-5

OpenAI

Grok 4.1 Fast

xAI

DescriptionOpenAI's August 2025 unified frontier model that auto-routes between a fast model and a deeper "thinking" variant.Grok 4.1 Fast is an AI model from xAI.
FamilyGPT 5Grok
ParamsUndisclosed (closed)-
Open weightsclosedclosed
LicenseProprietaryproprietary
Released7 Aug 202519 Nov 2025
Context400,000-
Input $/1M--
Output $/1M--
Cache read $/1M$0.125-
Cache write $/1M--
Speed0 tok/s0 tok/s
Latency0.00 s0.00 s
Modalitiestext, image, filetext
Providersopenai-
PublisherOpenAIxAI
Reported scores
Infraresolutionbench80.2% (150 samples)
Agent Diff Bench62.0% (179 samples)
Medpt100.0% (15 samples)
Hanabi11.8 (15 samples)
SciCode29.6% (AA)

FAQ

Is GPT-5 or Grok 4.1 Fast better?
Across the 20 benchmarks both models report on Sophon, GPT-5 leads on 17 of them. Which one is "better" depends on the benchmark - the table above shows every shared score.
How do GPT-5 and Grok 4.1 Fast compare on GPQA Diamond?
GPT-5 scores 68.6% and Grok 4.1 Fast scores 63.7% on GPQA Diamond.
When were GPT-5 and Grok 4.1 Fast released?
GPT-5 was released 7 Aug 2025 by OpenAI. Grok 4.1 Fast was released 19 Nov 2025 by xAI.

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