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Model comparison

Claude Opus 4.6 vs GPT-5.5 Pro

Data verified

Head-to-head evidence from 6 shared benchmark results across 4 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.

68.59/100
Margin
4.9pts
← winning
63.69/100
1 category wins2 category wins

Public leaderboard positions: Claude Opus 4.6 #16 (Supported); GPT-5.5 Pro #38 (Estimated). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.

Evidence parity. Claude Opus 4.6 and GPT-5.5 Pro share 6 comparable benchmark results. 3 of 8 categories are comparable. 40 results are unique to Claude Opus 4.6; 1 to GPT-5.5 Pro.

Updated July 22, 2026
Shared results
6
Claude Opus 4.6 only
40
GPT-5.5 Pro only
1
Comparable categories
3 / 8

Pick Claude Opus 4.6 if you want the stronger benchmark profile. GPT-5.5 Pro only becomes the better choice if agentic is the priority or you want the stronger reasoning-first profile.

Confidence note. This is a partial-evidence comparison with 6 shared benchmark results across 4 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

Claude Opus 4.6 is clearly ahead on the BenchAlign aggregate, 68.59 to 63.69. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.

Claude Opus 4.6's sharpest advantage is in knowledge, where it averages 69.1 against 57.2. The single biggest benchmark swing on the page is FrontierMath v2 (Tier 4), 22.900% to 39.600%. GPT-5.5 Pro does hit back in agentic, so the answer changes if that is the part of the workload you care about most.

GPT-5.5 Pro is also the more expensive model on tokens at $30.00 input / $180.00 output per 1M tokens, versus $5.00 input / $25.00 output per 1M tokens for Claude Opus 4.6. That is roughly 7.2x on output cost alone. GPT-5.5 Pro is the reasoning model in the pair, while Claude Opus 4.6 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 Claude Opus 4.6 and GPT-5.5 Pro
CategoryClaude Opus 4.6ΔGPT-5.5 Pro
AgenticClaude Opus 4.673.0Margin 17.1GPT-5.5 Pro90.1
KnowledgeClaude Opus 4.669.1Margin 11.9GPT-5.5 Pro57.2
MathClaude Opus 4.636.3Margin 11.8GPT-5.5 Pro48.1
CodingClaude Opus 4.668.1MarginNo overlapGPT-5.5 ProNot measured
MultimodalClaude Opus 4.677.3MarginNo overlapGPT-5.5 ProNot measured

Decisive benchmark drivers

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

More
A · Claude Opus 4.6B · GPT-5.5 Pro
  1. FrontierMath v2 (Tier 4)

    Math
    Source ↗
    A 22.900%B 39.600%
    Winner: GPT-5.5 ProΔ 16.7
    FrontierMath v2 (Tier 4): Claude Opus 4.6 scored 22.900%; GPT-5.5 Pro scored 39.600%. GPT-5.5 Pro wins this benchmark.
  2. FrontierMath v2 (Tiers 1-3)

    Math
    Source ↗
    A 40.700%B 51.000%
    Winner: GPT-5.5 ProΔ 10.3
    FrontierMath v2 (Tiers 1-3): Claude Opus 4.6 scored 40.700%; GPT-5.5 Pro scored 51.000%. GPT-5.5 Pro wins this benchmark.
  3. BrowseComp

    Agentic
    Source ↗
    A 83.7%B 90.1%
    Winner: GPT-5.5 ProΔ 6.4
    BrowseComp: Claude Opus 4.6 scored 83.7%; GPT-5.5 Pro scored 90.1%. GPT-5.5 Pro wins this benchmark.
  4. HLE

    Knowledge
    Source ↗
    A 53%B 57.2%
    Winner: GPT-5.5 ProΔ 4.2
    HLE: Claude Opus 4.6 scored 53%; GPT-5.5 Pro scored 57.2%. GPT-5.5 Pro wins this benchmark.

Operational comparison

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

MetricClaude Opus 4.6GPT-5.5 ProComparison
Input / output priceUSD per 1M tokensClaude Opus 4.6$5 input / $25 outputGPT-5.5 Pro$30 input / $180 outputClaude Opus 4.6 has the lower combined listed price.
Generation speedtokens per secondClaude Opus 4.640 tok/sGPT-5.5 ProNot availableA complete speed comparison is not available.
First-answer latencyseconds to first tokenClaude Opus 4.61.78 sGPT-5.5 ProNot availableA complete latency comparison is not available.
Context windowmaximum listed tokensClaude Opus 4.61MGPT-5.5 Pro1MListed context windows are equal.

Benchmark Deep Dive

AgenticGPT-5.5 Pro wins
BenchmarkClaude Opus 4.6GPT-5.5 ProResult
Terminal-Bench 2.0Source 65.4%Not comparable
BrowseCompSource 83.7%90.1%GPT-5.5 Pro leads
OSWorld-VerifiedSource 72.7%Not comparable
τ²-bench resultsSource 84.8%Not comparable
Claw-EvalSource 70.4%Not comparable
DeepSearchQASource 73.7%Not comparable
CyberGymSource 66.6%Not comparable
Gert LabsSource 61.85%Not comparable
ResearchClawBenchSource 19.9%Not comparable
JobBenchSource 36.7%Not comparable
Coding
BenchmarkClaude Opus 4.6GPT-5.5 ProResult
SWE-bench VerifiedSource 80.8%Not comparable
SWE-bench Verified*Source 75.6%Not comparable
LiveCodeBench ProSource 70.7%Not comparable
SWE-bench ProSource 53.4%Not comparable
SWE-RebenchSource 65.3%Not comparable
React Native EvalsSource 84.1%Not comparable
Vibe Code BenchSource 57.57%Not comparable
AA-SciCodeSource 45.7%Not comparable
FrontierCode 1.1 MainSource 26.9%Not comparable
Reasoning
BenchmarkClaude Opus 4.6GPT-5.5 ProResult
AA-LCRSource 58.3%Not comparable
CritPtSource 2.8%30.6%GPT-5.5 Pro leads
KnowledgeClaude Opus 4.6 wins
BenchmarkClaude Opus 4.6GPT-5.5 ProResult
GPQASource 91.3%Not comparable
GPQA-DSource 89.2%Not comparable
SuperGPQASource 95%Not comparable
MMLU-ProSource 82%Not comparable
MMLU-Pro (Arcee)Source 89.1%Not comparable
HLESource 53%57.2%GPT-5.5 Pro leads
HLE w/o toolsSource 40%43.1%GPT-5.5 Pro leads
HealthBench HardSource 14.8%Not comparable
MedXpertQA (Text)Source 52.1%Not comparable
Artificial Analysis Intelligence IndexSource 37.8%Not comparable
AA-GPQA DiamondSource 84.0%Not comparable
AA-HLESource 18.6%Not comparable
AA-Omniscience IndexSource 3.5%Not comparable
AA-Omniscience AccuracySource 45.2%Not comparable
AA-Omniscience Hallucination RateSource 76.0%Not comparable
MathGPT-5.5 Pro wins
BenchmarkClaude Opus 4.6GPT-5.5 ProResult
AIME25 (Arcee)Source 99.8%Not comparable
FrontierMath v2 (Tiers 1-3)Source 40.700%51.000%GPT-5.5 Pro leads
FrontierMath v2 (Tier 4)Source 22.900%39.600%GPT-5.5 Pro leads
FrontierMath (legacy)Source 52.4%Not comparable
Multimodal
BenchmarkClaude Opus 4.6GPT-5.5 ProResult
MMMU-ProSource 77.3%Not comparable
ERQASource 51.6%Not comparable
ScreenSpot ProSource 83.1%Not comparable
MedXpertQA (MM)Source 64.8%Not comparable
AA-MMMU-ProSource 72.5%Not comparable
Design Arena WebsiteSource 1325Not comparable
Inst. Following
BenchmarkClaude Opus 4.6GPT-5.5 ProResult
AA-IFBenchSource 44.6%Not comparable
Frequently Asked Questions (4)

Which is better, Claude Opus 4.6 or GPT-5.5 Pro?

Claude Opus 4.6 is ahead on BenchLM's BenchAlign leaderboard, 68.59 to 63.69. The biggest single separator in this matchup is FrontierMath v2 (Tier 4), where the scores are 22.900% and 39.600%.

Which is better for knowledge tasks, Claude Opus 4.6 or GPT-5.5 Pro?

Claude Opus 4.6 has the edge for knowledge tasks in this comparison, averaging 69.1 versus 57.2. Inside this category, HLE is the benchmark that creates the most daylight between them.

Which is better for math, Claude Opus 4.6 or GPT-5.5 Pro?

GPT-5.5 Pro has the edge for math in this comparison, averaging 48.1 versus 36.3. Inside this category, FrontierMath v2 (Tier 4) is the benchmark that creates the most daylight between them.

Which is better for agentic tasks, Claude Opus 4.6 or GPT-5.5 Pro?

GPT-5.5 Pro has the edge for agentic tasks in this comparison, averaging 90.1 versus 73. Inside this category, BrowseComp is the benchmark that creates the most daylight between them.

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Last updated: July 22, 2026

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