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Model comparison

Claude Opus 5 vs GPT-5.6 Luna

Data verified

Head-to-head evidence from 25 shared benchmark results across 5 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.

Anthropic
85.88/100
Margin
19.3pts
← winning
66.59/100
3 category wins2 category wins

Public leaderboard positions: Claude Opus 5 #1 (Estimated); GPT-5.6 Luna #24 (Estimated). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.

Evidence parity. Claude Opus 5 and GPT-5.6 Luna share 25 comparable benchmark results. 5 of 8 categories are comparable. 54 results are unique to Claude Opus 5; 17 to GPT-5.6 Luna.

Updated July 24, 2026
Shared results
25
Claude Opus 5 only
54
GPT-5.6 Luna only
17
Comparable categories
5 / 8

Pick Claude Opus 5 if you want the stronger benchmark profile. GPT-5.6 Luna only becomes the better choice if knowledge is the priority or you want the cheaper token bill.

Confidence note. This is a partial-evidence comparison with 25 shared benchmark results across 5 evidence categories; 5 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 5 is clearly ahead on the BenchAlign aggregate, 85.88 to 66.59. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.

Claude Opus 5's sharpest advantage is in reasoning, where it averages 90.4 against 59.5. The single biggest benchmark swing on the page is ARC-AGI-2, 90.4% to 59.5%. GPT-5.6 Luna does hit back in knowledge, so the answer changes if that is the part of the workload you care about most.

Claude Opus 5 is also the more expensive model on tokens at $5.00 input / $25.00 output per 1M tokens, versus $1.00 input / $6.00 output per 1M tokens for GPT-5.6 Luna. That is roughly 4.2x on output cost alone.

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 5 and GPT-5.6 Luna
CategoryClaude Opus 5ΔGPT-5.6 Luna
ReasoningClaude Opus 590.4Margin 30.9GPT-5.6 Luna59.5
KnowledgeClaude Opus 564.7Margin 27.6GPT-5.6 Luna92.3
CodingClaude Opus 589.5Margin 26.8GPT-5.6 Luna62.7
MultimodalClaude Opus 566.9Margin 11.5GPT-5.6 Luna78.4
AgenticClaude Opus 590.8Margin 6.7GPT-5.6 Luna84.1
MathClaude Opus 5Not measuredMarginNo overlapGPT-5.6 Luna73.6

Decisive benchmark drivers

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

More
A · Claude Opus 5B · GPT-5.6 Luna
  1. ARC-AGI-2

    Reasoning
    Source ↗
    A 90.4%B 59.5%
    Winner: Claude Opus 5Δ 30.9
    ARC-AGI-2: Claude Opus 5 scored 90.4%; GPT-5.6 Luna scored 59.5%. Claude Opus 5 wins this benchmark.
  2. SWE-bench Pro

    Coding
    Source ↗
    A 79.2%B 62.7%
    Winner: Claude Opus 5Δ 16.5
    SWE-bench Pro: Claude Opus 5 scored 79.2%; GPT-5.6 Luna scored 62.7%. Claude Opus 5 wins this benchmark.
  3. BrowseComp

    Agentic
    Source ↗
    A 90.8%B 83.3%
    Winner: Claude Opus 5Δ 7.5
    BrowseComp: Claude Opus 5 scored 90.8%; GPT-5.6 Luna scored 83.3%. Claude Opus 5 wins this benchmark.

Operational comparison

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

MetricClaude Opus 5GPT-5.6 LunaComparison
Input / output priceUSD per 1M tokensClaude Opus 5$5 input / $25 outputGPT-5.6 Luna$1 input / $6 outputGPT-5.6 Luna has the lower combined listed price.
Generation speedtokens per secondClaude Opus 5Not availableGPT-5.6 LunaNot availableA complete speed comparison is not available.
First-answer latencyseconds to first tokenClaude Opus 5Not availableGPT-5.6 LunaNot availableA complete latency comparison is not available.
Context windowmaximum listed tokensClaude Opus 5Not availableGPT-5.6 Luna1MA complete context comparison is not available.

Benchmark Deep Dive

AgenticClaude Opus 5 wins
BenchmarkClaude Opus 5GPT-5.6 LunaResult
FrontierBench v0.1Source 43.3%Not comparable
BrowseCompSource 90.8%83.3%Claude Opus 5 leads
HLE w/ toolsSource 64.7%Not comparable
DeepSearchQASource 95.0%Not comparable
DRACOSource 88.6%Not comparable
BrowseComp (10-agent, prerelease)Source 93.6%Not comparable
OSWorld 2.0Source 70.6%45.6%Claude Opus 5 leads
MCP AtlasSource 85.8%Not comparable
MCP-Atlas claim coverageSource 89.1%Not comparable
LAB all-pass (Anthropic harness)Source 23.58%Not comparable
LAB criterion-pass (Anthropic harness)Source 93.74%Not comparable
LAB all-pass (Harvey held-out)Source 11.7%Not comparable
LAB criterion-pass (Harvey held-out)Source 94.1%Not comparable
GDPval-AASource 18611582Claude Opus 5 leads
Toolathlon-VerifiedSource 80.6%Not comparable
Toolathlon Verified Pass@3Source 87.0%Not comparable
Toolathlon Verified Pass³Source 73.1%Not comparable
Toolathlon Verified avg. turnsSource 23.5 turnsNot comparable
AutomationBenchSource 26.0%Not comparable
AA Agentic IndexSource 55.3%45.6%Claude Opus 5 leads
GDPval-AASource 68.0%54.1%Claude Opus 5 leads
AA Tau3 BankingSource 30.3%27.2%Claude Opus 5 leads
AA BriefcaseSource 1720Not comparable
aaTerminalBench21Source 89.1%80.9%Claude Opus 5 leads
Terminal-Bench 2.0Source 84.7%Not comparable
CyberGymSource 77.9%Not comparable
ExploitGymSource 12.4%Not comparable
ToolathlonSource 53.4%Not comparable
AA Harvey LABSource 87.9%Not comparable
AA ITBenchSource 40.3%Not comparable
AA AutomationBenchSource 42.2%Not comparable
APEX-Agents-AASource 35.8%Not comparable
CodingClaude Opus 5 wins
BenchmarkClaude Opus 5GPT-5.6 LunaResult
SWE-bench VerifiedSource 96%Not comparable
SWE-bench ProSource 79.2%62.7%Claude Opus 5 leads
SWE MultilingualSource 89.5%Not comparable
SWE MultimodalSource 59.4%Not comparable
deepSweSource 68.8%67.2%Claude Opus 5 leads
FrontierCode 1.1 MainSource 53.4%Not comparable
FrontierCode 1.1 ExtendedSource 63.6%55.1%Claude Opus 5 leads
ProgramBench (episode 1)Source 83.0%Not comparable
ProgramBenchSource 93.0%Not comparable
cursorBench32Source 70.0%61.1%Claude Opus 5 leads
AA Coding IndexSource 78.0%71.5%Claude Opus 5 leads
AA-SciCodeSource 55.7%52.5%Claude Opus 5 leads
Terminal-Bench 2.0Source 84.7%Not comparable
ReasoningClaude Opus 5 wins
BenchmarkClaude Opus 5GPT-5.6 LunaResult
ARC-AGI-1Source 97.50%Not comparable
ARC-AGI-2Source 90.4%59.5%Claude Opus 5 leads
ARC-AGI-3Source 30.2%0.2%Claude Opus 5 leads
AA-LCRSource 70.0%74.0%GPT-5.6 Luna leads
CritPtSource 29.1%20.6%Claude Opus 5 leads
KnowledgeGPT-5.6 Luna wins
BenchmarkClaude Opus 5GPT-5.6 LunaResult
HLESource 64.7%Not comparable
HLE w/o toolsSource 56.3%Not comparable
HealthBench (raw)Source 67.1%Not comparable
HealthBench (length-adjusted)Source 57.8%Not comparable
HealthBench ProfessionalSource 59.8%55.7%Claude Opus 5 leads
HealthBench Professional (raw)Source 73.4%Not comparable
BioMysteryBench (human-solvable)Source 90.1%Not comparable
BioMysteryBench (human-difficult)Source 49.4%Not comparable
SpatialBench VerifiedSource 72.5%Not comparable
SingleCellBenchSource 60.6%Not comparable
ProteinGym HardSource 47.7%Not comparable
Protein DesignSource 42.5%Not comparable
Organic chemistry V2Source 61.6%Not comparable
Protocols (troubleshooting)Source 61.1%Not comparable
Protocols (understanding)Source 78.4%Not comparable
Artificial Analysis Intelligence IndexSource 60.7%51.2%Claude Opus 5 leads
AA-GPQA DiamondSource 93.2%91.1%Claude Opus 5 leads
AA-HLESource 52.6%37.2%Claude Opus 5 leads
AA-Omniscience IndexSource 31.3%-11.2%Claude Opus 5 leads
AA-Omniscience AccuracySource 54.2%41.5%Claude Opus 5 leads
AA-Omniscience Hallucination RateSource 50.1%90.1%Claude Opus 5 leads
GPQASource 92.3%Not comparable
GPQA-DSource 92.3%Not comparable
HealthBench HardSource 32.0%Not comparable
Math
BenchmarkClaude Opus 5GPT-5.6 LunaResult
IMO 2026Source 42/42Not comparable
RiemannBench (no tools)Source 60.0%Not comparable
RiemannBench (tools)Source 79.0%Not comparable
ArXivMath Jun. 2026 (no tools)Source 90.8%Not comparable
ArXivMath Jun. 2026 (tools)Source 91.3%Not comparable
FrontierMath (legacy)Source 78.6%Not comparable
FrontierMath v2 (Tiers 1-3)Source 78.600%Not comparable
FrontierMath v2 (Tier 4)Source 58.500%Not comparable
Multilingual
BenchmarkClaude Opus 5GPT-5.6 LunaResult
GMMLUSource 92.5%Not comparable
MILUSource 92.1%Not comparable
INCLUDESource 89.8%Not comparable
MultimodalGPT-5.6 Luna wins
BenchmarkClaude Opus 5GPT-5.6 LunaResult
Chartography (no tools)Source 29.6%Not comparable
Chartography (tools)Source 83.0%Not comparable
BenchCAD Vision2Code (no tools)Source 0.366Not comparable
BenchCAD Vision2Code (tools)Source 0.821Not comparable
GDP.pdf (no tools)Source 83.4%Not comparable
GDP.pdf (tools)Source 85.5%Not comparable
OfficeQASource 78.1%Not comparable
OfficeQA ProSource 66.9%Not comparable
AA-MMMU-ProSource 84.7%78.6%Claude Opus 5 leads
MMMU-ProSource 78.4%Not comparable
MMMU-Pro w/ PythonSource 79.5%Not comparable
Frequently Asked Questions (6)

Which is better, Claude Opus 5 or GPT-5.6 Luna?

Claude Opus 5 is ahead on BenchLM's BenchAlign leaderboard, 85.88 to 66.59. The biggest single separator in this matchup is ARC-AGI-2, where the scores are 90.4% and 59.5%.

Which is better for knowledge tasks, Claude Opus 5 or GPT-5.6 Luna?

GPT-5.6 Luna has the edge for knowledge tasks in this comparison, averaging 92.3 versus 64.7. Inside this category, AA-Omniscience Index is the benchmark that creates the most daylight between them.

Which is better for coding, Claude Opus 5 or GPT-5.6 Luna?

Claude Opus 5 has the edge for coding in this comparison, averaging 89.5 versus 62.7. Inside this category, SWE-bench Pro is the benchmark that creates the most daylight between them.

Which is better for reasoning, Claude Opus 5 or GPT-5.6 Luna?

Claude Opus 5 has the edge for reasoning in this comparison, averaging 90.4 versus 59.5. Inside this category, ARC-AGI-2 is the benchmark that creates the most daylight between them.

Which is better for agentic tasks, Claude Opus 5 or GPT-5.6 Luna?

Claude Opus 5 has the edge for agentic tasks in this comparison, averaging 90.8 versus 84.1. Inside this category, GDPval-AA is the benchmark that creates the most daylight between them.

Which is better for multimodal and grounded tasks, Claude Opus 5 or GPT-5.6 Luna?

GPT-5.6 Luna has the edge for multimodal and grounded tasks in this comparison, averaging 78.4 versus 66.9. Inside this category, AA-MMMU-Pro is the benchmark that creates the most daylight between them.

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Last updated: July 24, 2026