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Model comparison

Gemini 2.5 Pro vs GPT-5.1

Data verified

Head-to-head evidence from 21 shared benchmark results across 7 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.

57.25/100
Margin
3.6pts
← winning
GPT-5.1
OpenAI
53.65/100
0 category wins1 category wins

Public leaderboard positions: Gemini 2.5 Pro #70 (Supported); GPT-5.1 #94 (Estimated). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.

Evidence parity. Gemini 2.5 Pro and GPT-5.1 share 21 comparable benchmark results. 1 of 8 categories are comparable. 3 results are unique to Gemini 2.5 Pro; 0 to GPT-5.1.

Updated July 20, 2026
Shared results
21
Gemini 2.5 Pro only
3
GPT-5.1 only
0
Comparable categories
1 / 8

Pick Gemini 2.5 Pro if you want the stronger benchmark profile. GPT-5.1 only becomes the better choice if mathematics is the priority or you want the stronger reasoning-first profile.

Confidence note. This is a partial-evidence comparison with 21 shared benchmark results across 7 evidence categories; 1 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.

Why this result

Gemini 2.5 Pro is clearly ahead on the BenchAlign aggregate, 57.25 to 53.65. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.

GPT-5.1 is the reasoning model in the pair, while Gemini 2.5 Pro is not. That usually helps on harder chain-of-thought-heavy tests, but it can also mean more latency and more token spend in real use. Gemini 2.5 Pro gives you the larger context window at 1M, compared with 200K for GPT-5.1.

Category breakdown

Exact category averages are shown below. Not measured means BenchLM does not have enough sourced public coverage for that model and category.

Category scores and score margins for Gemini 2.5 Pro and GPT-5.1
CategoryGemini 2.5 ProΔGPT-5.1
MathGemini 2.5 Pro11.6Margin→ 14.8GPT-5.126.4
CodingGemini 2.5 Pro63.8MarginNo overlapGPT-5.1Not measured
KnowledgeGemini 2.5 Pro27.4MarginNo overlapGPT-5.1Not measured

Decisive benchmark drivers

The largest measured benchmark gaps in this matchup, with exact reported values.

More
A · Gemini 2.5 ProB · GPT-5.1

  1. FrontierMath v2 (Tiers 1-3)

    Math
    Source ↗
    A 14.138%B 31.034%
    Winner: GPT-5.1Δ 16.9
    FrontierMath v2 (Tiers 1-3): Gemini 2.5 Pro scored 14.138%; GPT-5.1 scored 31.034%. GPT-5.1 wins this benchmark.

  2. FrontierMath v2 (Tier 4)

    Math
    Source ↗
    A 4.167%B 12.500%
    Winner: GPT-5.1Δ 8.3
    FrontierMath v2 (Tier 4): Gemini 2.5 Pro scored 4.167%; GPT-5.1 scored 12.500%. GPT-5.1 wins this benchmark.

Operational comparison

Runtime and commercial metrics are compared only when both models have a complete sourced value.

MetricGemini 2.5 ProGPT-5.1Comparison
Input / output priceUSD per 1M tokensGemini 2.5 Pro$1.25 input / $10 outputGPT-5.1$1.25 input / $10 outputListed prices are equal.
Generation speedtokens per secondGemini 2.5 Pro117 tok/sGPT-5.1111 tok/sGemini 2.5 Pro has the higher measured throughput.
First-answer latencyseconds to first tokenGemini 2.5 Pro21.19 sGPT-5.157.47 sGemini 2.5 Pro reaches the first token sooner.
Context windowmaximum listed tokensGemini 2.5 Pro1MGPT-5.1200KGemini 2.5 Pro lists the larger context window.

Benchmark Deep Dive

Agentic
BenchmarkGemini 2.5 ProGPT-5.1Result
AA Agentic IndexSource 7.1%21.0%GPT-5.1 leads
τ²-bench resultsSource 54.1%81.9%GPT-5.1 leads
Gert LabsSource 42.01%41.24%Gemini 2.5 Pro leads
GDPval-AASource 8.3%24.4%GPT-5.1 leads
GDPval-AASource 665987GPT-5.1 leads
Coding
BenchmarkGemini 2.5 ProGPT-5.1Result
SWE-bench VerifiedSource 63.8%—Not comparable
Vibe Code BenchSource 0.40%24.61%GPT-5.1 leads
AA Coding IndexSource 33.3%49.4%GPT-5.1 leads
AA-SciCodeSource 42.8%43.3%GPT-5.1 leads
Reasoning
BenchmarkGemini 2.5 ProGPT-5.1Result
AA-LCRSource 66.0%75.0%GPT-5.1 leads
CritPtSource 2.6%4.9%GPT-5.1 leads
Knowledge
BenchmarkGemini 2.5 ProGPT-5.1Result
GPQASource 83%—Not comparable
HLESource 18.8%—Not comparable
Artificial Analysis Intelligence IndexSource 25.8%36.9%GPT-5.1 leads
AA-GPQA DiamondSource 84.4%87.3%GPT-5.1 leads
AA-HLESource 21.1%26.5%GPT-5.1 leads
AA-Omniscience IndexSource -14.3%5.6%GPT-5.1 leads
AA-Omniscience AccuracySource 39.0%37.6%Gemini 2.5 Pro leads
AA-Omniscience Hallucination RateSource 87.4%51.3%GPT-5.1 leads
MathGPT-5.1 wins
BenchmarkGemini 2.5 ProGPT-5.1Result
FrontierMath v2 (Tiers 1-3)Source 14.138%31.034%GPT-5.1 leads
FrontierMath v2 (Tier 4)Source 4.167%12.500%GPT-5.1 leads
Multimodal
BenchmarkGemini 2.5 ProGPT-5.1Result
AA-MMMU-ProSource 74.9%75.5%GPT-5.1 leads
Design Arena WebsiteSource 11991220GPT-5.1 leads
Inst. Following
BenchmarkGemini 2.5 ProGPT-5.1Result
AA-IFBenchSource 48.7%72.9%GPT-5.1 leads
Frequently Asked Questions (2)

Which is better, Gemini 2.5 Pro or GPT-5.1?

Gemini 2.5 Pro is ahead on BenchLM's BenchAlign leaderboard, 57.25 to 53.65. The biggest single separator in this matchup is FrontierMath v2 (Tiers 1-3), where the scores are 14.138% and 31.034%.

Which is better for math, Gemini 2.5 Pro or GPT-5.1?

GPT-5.1 has the edge for math in this comparison, averaging 26.4 versus 11.6. Inside this category, FrontierMath v2 (Tiers 1-3) is the benchmark that creates the most daylight between them.

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Last updated: July 20, 2026

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