Skip to main content
BenchLM
Advertise

Model comparison

Gemini 2.5 Pro vs GPT-5.5

Data verified

Head-to-head evidence from 23 shared benchmark results across 7 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.

57.25/100
Margin
16.3pts
winning →
GPT-5.5
OpenAI
73.51/100
1 category wins2 category wins

Public leaderboard positions: Gemini 2.5 Pro #70 (Supported); GPT-5.5 #9 (Estimated). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.

Evidence parity. Gemini 2.5 Pro and GPT-5.5 share 23 comparable benchmark results. 3 of 8 categories are comparable. 1 result is unique to Gemini 2.5 Pro; 34 to GPT-5.5.

Updated July 22, 2026
Shared results
23
Gemini 2.5 Pro only
1
GPT-5.5 only
34
Comparable categories
3 / 8

Pick GPT-5.5 if you want the stronger benchmark profile. Gemini 2.5 Pro only becomes the better choice if coding is the priority or you want the cheaper token bill.

Confidence note. This is a partial-evidence comparison with 23 shared benchmark results across 7 evidence categories; 3 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.

Why this result

GPT-5.5 is clearly ahead on the BenchAlign aggregate, 73.51 to 57.25. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.

GPT-5.5's sharpest advantage is in mathematics, where it averages 47.6 against 11.6. The single biggest benchmark swing on the page is FrontierMath v2 (Tiers 1-3), 14.138% to 51.700%. Gemini 2.5 Pro does hit back in coding, so the answer changes if that is the part of the workload you care about most.

GPT-5.5 is also the more expensive model on tokens at $5.00 input / $30.00 output per 1M tokens, versus $1.25 input / $10.00 output per 1M tokens for Gemini 2.5 Pro. That is roughly 3.0x on output cost alone. GPT-5.5 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.

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-5.5
CategoryGemini 2.5 ProΔGPT-5.5
MathGemini 2.5 Pro11.6Margin→ 36.0GPT-5.547.6
KnowledgeGemini 2.5 Pro27.4Margin→ 30.4GPT-5.557.8
CodingGemini 2.5 Pro63.8Margin← 5.2GPT-5.558.6
AgenticGemini 2.5 ProNot measuredMarginNo overlapGPT-5.581.6
ReasoningGemini 2.5 ProNot measuredMarginNo overlapGPT-5.585.0
MultimodalGemini 2.5 ProNot measuredMarginNo overlapGPT-5.570.4

Decisive benchmark drivers

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

More
A · Gemini 2.5 ProB · GPT-5.5

  1. FrontierMath v2 (Tiers 1-3)

    Math
    Source ↗
    A 14.138%B 51.700%
    Winner: GPT-5.5Δ 37.6
    FrontierMath v2 (Tiers 1-3): Gemini 2.5 Pro scored 14.138%; GPT-5.5 scored 51.700%. GPT-5.5 wins this benchmark.

  2. HLE

    Knowledge
    Source ↗
    A 18.8%B 52.2%
    Winner: GPT-5.5Δ 33.4
    HLE: Gemini 2.5 Pro scored 18.8%; GPT-5.5 scored 52.2%. GPT-5.5 wins this benchmark.

  3. FrontierMath v2 (Tier 4)

    Math
    Source ↗
    A 4.167%B 35.400%
    Winner: GPT-5.5Δ 31.2
    FrontierMath v2 (Tier 4): Gemini 2.5 Pro scored 4.167%; GPT-5.5 scored 35.400%. GPT-5.5 wins this benchmark.

  4. GPQA

    Knowledge
    Source ↗
    A 83%B 93.6%
    Winner: GPT-5.5Δ 10.6
    GPQA: Gemini 2.5 Pro scored 83%; GPT-5.5 scored 93.6%. GPT-5.5 wins this benchmark.

Operational comparison

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

MetricGemini 2.5 ProGPT-5.5Comparison
Input / output priceUSD per 1M tokensGemini 2.5 Pro$1.25 input / $10 outputGPT-5.5$5 input / $30 outputGemini 2.5 Pro has the lower combined listed price.
Generation speedtokens per secondGemini 2.5 Pro117 tok/sGPT-5.5Not availableA complete speed comparison is not available.
First-answer latencyseconds to first tokenGemini 2.5 Pro21.19 sGPT-5.5Not availableA complete latency comparison is not available.
Context windowmaximum listed tokensGemini 2.5 Pro1MGPT-5.51MListed context windows are equal.

Benchmark Deep Dive

Agentic
BenchmarkGemini 2.5 ProGPT-5.5Result
AA Agentic IndexSource 7.1%44.9%GPT-5.5 leads
τ²-bench resultsSource 54.1%93.9%GPT-5.5 leads
Gert LabsSource 42.01%72.93%GPT-5.5 leads
GDPval-AASource 8.3%49.5%GPT-5.5 leads
GDPval-AASource 6651490GPT-5.5 leads
Terminal-Bench 2.0Source —82%Not comparable
CyberGymSource —81.8%Not comparable
BrowseCompSource —84.4%Not comparable
OSWorld-VerifiedSource —78.7%Not comparable
MCP AtlasSource —75.3%Not comparable
ToolathlonSource —55.6%Not comparable
APEX-Agents-AASource —37.7%Not comparable
ResearchClawBenchSource —17.0%Not comparable
OSWorld 2.0Source —13.0%Not comparable
JobBenchSource —42.7%Not comparable
ExploitGymSource —13.4%Not comparable
AA BriefcaseSource —1154Not comparable
AA AutomationBenchSource —42.1%Not comparable
AA EnterpriseOps-GymSource —46.6%Not comparable
AA Harvey LABSource —86.3%Not comparable
AA ITBenchSource —45.8%Not comparable
AA Tau3 BankingSource —31.3%Not comparable
terminalBenchHardSource —60.6%Not comparable
aaTerminalBench21Source —84.3%Not comparable
CodingGemini 2.5 Pro wins
BenchmarkGemini 2.5 ProGPT-5.5Result
SWE-bench VerifiedSource 63.8%—Not comparable
Vibe Code BenchSource 0.40%69.85%GPT-5.5 leads
AA Coding IndexSource 33.3%74.9%GPT-5.5 leads
AA-SciCodeSource 42.8%56.1%GPT-5.5 leads
SWE-bench ProSource —58.6%Not comparable
Terminal-Bench 2.0Source —82.0%Not comparable
React Native EvalsSource —84.7%Not comparable
cursorBench31Source —59.2%Not comparable
cursorBench32Source —58.4%Not comparable
FrontierCode 1.1 MainSource —43.0%Not comparable
Reasoning
BenchmarkGemini 2.5 ProGPT-5.5Result
AA-LCRSource 66.0%74.3%GPT-5.5 leads
CritPtSource 2.6%27.1%GPT-5.5 leads
MRCR v2 64K-128KSource —83.1%Not comparable
MRCR v2 128K-256KSource —87.5%Not comparable
ARC-AGI-2Source —85%Not comparable
KnowledgeGPT-5.5 wins
BenchmarkGemini 2.5 ProGPT-5.5Result
GPQASource 83%93.6%GPT-5.5 leads
HLESource 18.8%52.2%GPT-5.5 leads
Artificial Analysis Intelligence IndexSource 25.8%54.8%GPT-5.5 leads
AA-GPQA DiamondSource 84.4%93.5%GPT-5.5 leads
AA-HLESource 21.1%44.3%GPT-5.5 leads
AA-Omniscience IndexSource -14.3%20.1%GPT-5.5 leads
AA-Omniscience AccuracySource 39.0%56.9%GPT-5.5 leads
AA-Omniscience Hallucination RateSource 87.4%85.5%GPT-5.5 leads
GPQA-DSource —93.6%Not comparable
HLE w/o toolsSource —41.4%Not comparable
MathGPT-5.5 wins
BenchmarkGemini 2.5 ProGPT-5.5Result
FrontierMath v2 (Tiers 1-3)Source 14.138%51.700%GPT-5.5 leads
FrontierMath v2 (Tier 4)Source 4.167%35.400%GPT-5.5 leads
FrontierMath (legacy)Source —51.7%Not comparable
Multimodal
BenchmarkGemini 2.5 ProGPT-5.5Result
AA-MMMU-ProSource 74.9%79.9%GPT-5.5 leads
Design Arena WebsiteSource 11971282GPT-5.5 leads
MMMU-ProSource —81.2%Not comparable
MMMU-Pro w/ PythonSource —83.2%Not comparable
OfficeQA ProSource —54.1%Not comparable
Inst. Following
BenchmarkGemini 2.5 ProGPT-5.5Result
AA-IFBenchSource 48.7%75.9%GPT-5.5 leads
Frequently Asked Questions (4)

Which is better, Gemini 2.5 Pro or GPT-5.5?

GPT-5.5 is ahead on BenchLM's BenchAlign leaderboard, 73.51 to 57.25. The biggest single separator in this matchup is FrontierMath v2 (Tiers 1-3), where the scores are 14.138% and 51.700%.

Which is better for knowledge tasks, Gemini 2.5 Pro or GPT-5.5?

GPT-5.5 has the edge for knowledge tasks in this comparison, averaging 57.8 versus 27.4. Inside this category, AA-Omniscience Index is the benchmark that creates the most daylight between them.

Which is better for coding, Gemini 2.5 Pro or GPT-5.5?

Gemini 2.5 Pro has the edge for coding in this comparison, averaging 63.8 versus 58.6. Inside this category, Vibe Code Bench is the benchmark that creates the most daylight between them.

Which is better for math, Gemini 2.5 Pro or GPT-5.5?

GPT-5.5 has the edge for math in this comparison, averaging 47.6 versus 11.6. Inside this category, FrontierMath v2 (Tiers 1-3) is the benchmark that creates the most daylight between them.

Related Comparisons

Explore More

Google Compare Pricing Methodology Find Your Best LLM Overall Rankings
Last updated: July 22, 2026

Choose a model with this week’s evidence

Join 2,000+ readers for ranking moves, pricing changes, and the claims that still need proof.

One email each week. Unsubscribe anytime.