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Claude Opus 4.5 vs GPT-5.5

GPT-5.5 leads Claude Opus 4.5 on coding, 71.3 to 44.0 on the Vibe Coding Index, and Claude Opus 4.5 costs 1.2x less per output token ($25.00 vs $30.00 per million). Updated October 21, 2026; 89 benchmarks have a result for both.

Replace Claude Opus 4.5 Replace GPT-5.5
Claude Opus 4.5Anthropic
Coding
44.0
Overall
55.7
Output $/M
$25.00
10
GPT-5.5OpenAI
Coding
71.3
Overall
69.2
Output $/M
$30.00
79
vs boards won of 89 shared

Claude Opus 4.5 or GPT-5.5: which to pick

Pick GPT-5.5 for coding: it scores 71.3 on the Vibe Coding Index against 44.0 for Claude Opus 4.5.

Pick Claude Opus 4.5 for output tokens 1.2x cheaper ($25.00 vs $30.00 per million) and a lower cost per solved task ($1.37 against $1.65).

Model AClaude Opus 4.5Anthropic44.0/1003 independent benchmarks$1.37 per solved taskModel BGPT-5.5OpenAI71.3/1005 independent benchmarks$1.65 per solved task
Shared results
89
Claude Opus 4.5 only
19
GPT-5.5 only
45
Like-for-like categories
8 of 9

Only benchmarks that tested both models count toward a pick; a result only one model has is shown but not compared.

Which one for your work

Each card is decided by one number both models carry. Where only one has it, the card says so and makes no call.

At a glance

Coding index
Claude Opus 4.5 44.0 from 3 benchmarks, GPT-5.5 71.3 from 5 benchmarks.
Widest category
Math, 23.8 points apart on average over 6 shared benchmarks.
Widest single gap
FrontierMath, tier 4: Claude Opus 4.5 4.9% against GPT-5.5 72.5%, 67.6 points apart on a 0 to 100 scale.
Output price
Claude Opus 4.5 $25.00 against GPT-5.5 $30.00 per million output tokens, 1.2x apart.
Context window
Claude Opus 4.5 takes 200K tokens, GPT-5.5 1.05M.

Benchmark by benchmark

First the score: boards each model leads, per category, where both have a result. Then every board, a category to a fold; bars are each result on a 0 to 100 scale, so compare the two in a row, not one row with another.

Boards won, where both have a result
CategoryClaude Opus 4.5BarsGPT-5.5Ties
Coding111
Intelligence02
Agentic work53
Reasoning015
Math15
Knowledge112
Web design17
General124
All shared boards1079
CodingLike-for-likeSix of these boards feed the Vibe Coding Index111
Coding benchmarks for Claude Opus 4.5 and GPT-5.5
BenchmarkClaude Opus 4.5GPT-5.5Leader
SWE-bench Verified79.2%Not measuredOnly Claude Opus 4.5 measured
SWE-bench (full test set)52.6%Not measuredOnly Claude Opus 4.5 measured
SWE-bench Multilingual70.7%Not measuredOnly Claude Opus 4.5 measured
LiveBench codingNot measured85.1%Only GPT-5.5 measured
LMArena WebDev14941513GPT-5.5
AA Coding IndexNot measured74.9Only GPT-5.5 measured
LiveCodeBench (Vals AI)83.7%85.3%GPT-5.5
SWE-bench Verified (Vals AI)76.4%82.6%GPT-5.5
Vibe Code Bench (Vals AI)20.6%69.8%GPT-5.5
Code migration (Vals AI)Not measured45.2%Only GPT-5.5 measured
ProgramBench (Vals AI)Not measured0.5%Only GPT-5.5 measured
Terminal-Bench 2.1 (Vals AI)Not measured76.4%Only GPT-5.5 measured
SkillsBench (Vals AI)Not measured62.5%Only GPT-5.5 measured
LiveCodeBench (Artificial Analysis run)87.1%Not measuredOnly Claude Opus 4.5 measured
SciCodeNot measured56.1%Only GPT-5.5 measured
Terminal-Bench Hard (Artificial Analysis run)47.0%60.6%GPT-5.5
Terminal-Bench63.1%84.7%GPT-5.5
FrontierCodeNot measured43.0%Only GPT-5.5 measured
GSO-Bench26.5%40.2%GPT-5.5
WeirdML63.7%84.9%GPT-5.5
MirrorCodeNot measured10.0%Only GPT-5.5 measured
Cybench82.0%Not measuredOnly Claude Opus 4.5 measured
ALE-BenchNot measured1943.0Only GPT-5.5 measured
LMArena Text: coding15031494Claude Opus 4.5
LMArena Text: software and IT14831493GPT-5.5
LMArena WebDev: React14781506GPT-5.5
LMArena WebDev: HTML15101543GPT-5.5
LMArena WebDev: from an imageNot measured1532Only GPT-5.5 measured
Neither model has a result on the other 11 boards here
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index02
Intelligence benchmarks for Claude Opus 4.5 and GPT-5.5
BenchmarkClaude Opus 4.5GPT-5.5Leader
AA Intelligence Index29.138.4GPT-5.5
Epoch Capabilities Index150.1159.7GPT-5.5
Agentic workLike-for-likePublic boards, shown as published, kept out of the index53
Agentic work benchmarks for Claude Opus 4.5 and GPT-5.5
BenchmarkClaude Opus 4.5GPT-5.5Leader
AA Agentic IndexNot measured36.4Only GPT-5.5 measured
Design Arena: agents building web apps11591117Claude Opus 4.5
Design Arena: agents building full-stack apps11561089Claude Opus 4.5
Design Arena: agents building mobile apps11891143Claude Opus 4.5
Design Arena: agents building Android apps11751163Claude Opus 4.5
Design Arena: agents building Godot gamesNot measured1173Only GPT-5.5 measured
Design Arena: agents building gamesNot measured1179Only GPT-5.5 measured
Design Arena: HTML slidesNot measured1067Only GPT-5.5 measured
Design Arena: PowerPoint slidesNot measured1109Only GPT-5.5 measured
LiveBench researchNot measured61.6%Only GPT-5.5 measured
LiveBench browserNot measured48.0%Only GPT-5.5 measured
LiveBench long agenticNot measured44.6%Only GPT-5.5 measured
SREBench (Vals AI)Not measured3.8%Only GPT-5.5 measured
Finance Agent (Vals AI)Not measured51.8%Only GPT-5.5 measured
Tax Agent Bench (Vals AI)Not measured21.8%Only GPT-5.5 measured
Legal Research Bench (Vals AI)Not measured40.4%Only GPT-5.5 measured
Excel Modeling Benchmark (Vals AI)Not measured64.5%Only GPT-5.5 measured
Time Horizon Index (Vals AI)Not measured8.3%Only GPT-5.5 measured
τ²-Bench Telecom89.5%93.9%GPT-5.5
APEX-AgentsNot measured55.1%Only GPT-5.5 measured
METR time horizons75.0%Not measuredOnly Claude Opus 4.5 measured
Remote Labor Index3.8%6.3%GPT-5.5
GDPval45.5%Not measuredOnly Claude Opus 4.5 measured
OSWorld 2.0Not measured13.0%Only GPT-5.5 measured
BALROG43.5%Not measuredOnly Claude Opus 4.5 measured
DeepResearch Bench54.8%54.0%Claude Opus 4.5
PostTrainBenchNot measured27.2%Only GPT-5.5 measured
OSWorld66.3%Not measuredOnly Claude Opus 4.5 measured
Vending-Bench 2$4,967$7,524GPT-5.5
Berkeley Function Calling Leaderboard (BFCL)77.5%Not measuredOnly Claude Opus 4.5 measured
Neither model has a result on the other 11 boards here
ReasoningLike-for-likePublic boards, shown as published, kept out of the index015
Reasoning benchmarks for Claude Opus 4.5 and GPT-5.5
BenchmarkClaude Opus 4.5GPT-5.5Leader
GPQA Diamond85.9%93.2%GPT-5.5
LiveBench reasoningNot measured89.7%Only GPT-5.5 measured
MMMU Pro (Vals AI)83.0%88.3%GPT-5.5
GPQA Diamond (Artificial Analysis run)86.6%93.5%GPT-5.5
Humanity's Last Exam (Artificial Analysis run)30.1%45.8%GPT-5.5
GPQA Diamond (Epoch AI run)86.0%90.7%GPT-5.5
ARC-AGI80.0%95.0%GPT-5.5
ARC-AGI-237.6%85.0%GPT-5.5
SimpleBench62.0%69.0%GPT-5.5
Chess puzzles14.0%63.0%GPT-5.5
Mystery game puzzles22.0%56.0%GPT-5.5
EBR-bench14.3%34.3%GPT-5.5
VPCT40.0%Not measuredOnly Claude Opus 4.5 measured
LMArena Text: hard prompts14761489GPT-5.5
LMArena Text: expert14871507GPT-5.5
LMArena Text: hard prompts in English14821483GPT-5.5
LMArena Vision: diagramsNot measured1325Only GPT-5.5 measured
LMArena Vision: homeworkNot measured1332Only GPT-5.5 measured
Kagi LLM Benchmark80.2%88.8%GPT-5.5
Neither model has a result on the other 3 boards here
MathLike-for-likePublic boards, shown as published, kept out of the index15
Math benchmarks for Claude Opus 4.5 and GPT-5.5
BenchmarkClaude Opus 4.5GPT-5.5Leader
AIME95.4%Not measuredOnly Claude Opus 4.5 measured
MGSM (Vals AI)95.2%Not measuredOnly Claude Opus 4.5 measured
AA Math Index91.3Not measuredOnly Claude Opus 4.5 measured
AIME 2025 (Artificial Analysis run)91.3%Not measuredOnly Claude Opus 4.5 measured
OTIS Mock AIME86.1%84.4%Claude Opus 4.5
FrontierMath, tiers 1 to 334.4%85.3%GPT-5.5
FrontierMath, tier 44.9%72.5%GPT-5.5
ProofBench36.0%50.0%GPT-5.5
LMArena Text: math14631487GPT-5.5
LMArena Text: mathematical work14681496GPT-5.5
Neither model has a result on the other 3 boards here
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index112
Knowledge benchmarks for Claude Opus 4.5 and GPT-5.5
BenchmarkClaude Opus 4.5GPT-5.5Leader
MMLU Pro87.3%88.1%GPT-5.5
LegalBench (Vals AI)84.6%86.5%GPT-5.5
CaseLaw (Vals AI)62.6%66.2%GPT-5.5
CorpFin (Vals AI)65.1%68.4%GPT-5.5
TaxEval (Vals AI)74.9%75.0%GPT-5.5
MortgageTax (Vals AI)68.7%68.8%GPT-5.5
MedQA (Vals AI)95.9%Not measuredOnly Claude Opus 4.5 measured
MedCode (Vals AI)49.2%49.1%Claude Opus 4.5
MMLU Pro (Artificial Analysis run)89.5%Not measuredOnly Claude Opus 4.5 measured
SimpleQA Verified45.7%63.0%GPT-5.5
GeoBench75.0%Not measuredOnly Claude Opus 4.5 measured
LMArena Text: science14541485GPT-5.5
LMArena Text: medicine and healthcare14441465GPT-5.5
LMArena Text: legal and government14591491GPT-5.5
LMArena Text: business and finance14481478GPT-5.5
FACTS Benchmark Suite43.9%66.7%GPT-5.5
Neither model has a result on the other 2 boards here
Web designLike-for-likePublic boards, shown as published, kept out of the index17
Web design benchmarks for Claude Opus 4.5 and GPT-5.5
BenchmarkClaude Opus 4.5GPT-5.5Leader
Design Arena: websites12471256GPT-5.5
Design Arena: UI components12381260GPT-5.5
Design Arena: game dev12291294GPT-5.5
Design Arena: data viz12431265GPT-5.5
Design Arena: 3D12141198Claude Opus 4.5
Design Arena: all code categories12421260GPT-5.5
Design Arena: SVG11811234GPT-5.5
Design Arena: ASCII art11901255GPT-5.5
LiveBench designNot measured70.3%Only GPT-5.5 measured
GeneralLike-for-likePublic boards, shown as published, kept out of the index124
General benchmarks for Claude Opus 4.5 and GPT-5.5
BenchmarkClaude Opus 4.5GPT-5.5Leader
LiveBench data analysisNot measured81.6%Only GPT-5.5 measured
Public Benefits Bench (Vals AI)Not measured60.9%Only GPT-5.5 measured
SAGE (Vals AI)52.1%51.5%Claude Opus 4.5
MedScribe (Vals AI)85.3%86.9%GPT-5.5
Vals Multimodal IndexNot measured68.1%Only GPT-5.5 measured
IFBench58.0%75.9%GPT-5.5
Long context reasoning (AA-LCR)77.3%84.3%GPT-5.5
DTBench89.9%96.0%GPT-5.5
LMCA44.5%54.3%GPT-5.5
CL-bench21.1%Not measuredOnly Claude Opus 4.5 measured
Surface Evolver BenchNot measured88.1%Only GPT-5.5 measured
Furniture assembly28.3%44.2%GPT-5.5
ExploitBenchNot measured47.4%Only GPT-5.5 measured
CL-bench LifeNot measured22.2%Only GPT-5.5 measured
LMArena Text14511471GPT-5.5
LMArena Text: instruction following14781478GPT-5.5
LMArena Text: creative writing14451455GPT-5.5
LMArena VisionNot measured1297Only GPT-5.5 measured
LMArena Text: English14611470GPT-5.5
LMArena Text: non-English14381467GPT-5.5
LMArena Text: Chinese14701534GPT-5.5
LMArena Text: German14491480GPT-5.5
LMArena Text: Japanese14171499GPT-5.5
LMArena Text: Korean14241460GPT-5.5
LMArena Text: French14711485GPT-5.5
LMArena Text: Spanish14571468GPT-5.5
LMArena Text: Russian14471473GPT-5.5
LMArena Text: Polish14391465GPT-5.5
LMArena Text: multi-turn14661476GPT-5.5
LMArena Text: longer queries14791484GPT-5.5
LMArena Text: writing and language14521466GPT-5.5
LMArena Text: entertainment and media14341449GPT-5.5
LMArena Vision: EnglishNot measured1292Only GPT-5.5 measured
LMArena Vision: ChineseNot measured1360Only GPT-5.5 measured
LMArena Vision: reading textNot measured1306Only GPT-5.5 measured
LMArena Vision: humorNot measured1293Only GPT-5.5 measured
LMArena Vision: recognizing thingsNot measured1231Only GPT-5.5 measured
LMArena Vision: creative writingNot measured1301Only GPT-5.5 measured
LMArena Document14621486GPT-5.5
Neither model has a result on the other 7 boards here
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
Image generation benchmarks for Claude Opus 4.5 and GPT-5.5
BenchmarkClaude Opus 4.5GPT-5.5Leader
Neither model has a result on 5 boards here

What each workload costs

Three fixed token mixes at each model's listed price, so per-token rates become a bill.

Chat turn

1K input + 500 output tokens

Claude Opus 4.5$0.018Fits in one request
GPT-5.5$0.020Fits in one request

Claude Opus 4.5 costs less

Repository review

50K input + 3K output tokens

Claude Opus 4.5$0.325Fits in one request
GPT-5.5$0.340Fits in one request

Claude Opus 4.5 costs less

Agent loop

200K input + 10K output tokens

Claude Opus 4.5$1.25Exceeds the context window
GPT-5.5$1.30Fits in one request

Claude Opus 4.5 costs less

Listed OpenRouter rates, without cache or batch discounts. A workload that does not fit a model's context window would need splitting.

Specification differences

The leading value in a row is marked; a row with a missing value names no leader. Our two rows are marked in red.

Specifications of Claude Opus 4.5 and GPT-5.5
SpecificationAnthropic Claude Opus 4.5OpenAI GPT-5.5
MakerAnthropicOpenAI
WeightsNo public weights listedNo public weights listed
ReleasedNovember 24, 2025April 24, 2026
Context window200K1.05M
Input $/Mtok$5.00$5.00
Output $/Mtok$25.00$30.00
Coding index44.071.3
Independent measurements behind it35
Cost per solved task$1.37$1.65
SourceOpenRouter listingOpenRouter listing

Questions

Is Claude Opus 4.5 better than GPT-5.5 for coding?

Pick GPT-5.5 for coding: it scores 71.3 on the Vibe Coding Index against 44.0 for Claude Opus 4.5. Pick Claude Opus 4.5 for output tokens 1.2x cheaper ($25.00 vs $30.00 per million) and a lower cost per solved task ($1.37 against $1.65).

Which is cheaper, Claude Opus 4.5 or GPT-5.5?

Claude Opus 4.5 costs $5.00 per million input tokens and $25.00 per million output tokens; GPT-5.5 costs $5.00 and $30.00. Per solved SWE-bench Verified task, Claude Opus 4.5 costs $1.37 and GPT-5.5 $1.65.

Which has the bigger context window, Claude Opus 4.5 or GPT-5.5?

GPT-5.5, with 1.05M tokens against 200K.

How many benchmarks is the Claude Opus 4.5 vs GPT-5.5 comparison based on?

89 benchmarks have a result for both models as of October 21, 2026. Claude Opus 4.5's coding index rests on 3 independent benchmarks and GPT-5.5's on 5. Where only one model has a result, the page says so instead of naming a winner.

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