Model comparison

Claude Opus 4.6 vs GPT-5.3 Chat

Claude Opus 4.6 is the stronger model overall, scoring 58.2 to 42.8 on the Noometry Index. GPT-5.3 Chat costs 2.1× less per token, which makes it the better buy when Claude Opus 4.6's lead doesn't matter for your workload.

Last verified . 18 shared benchmarks.

Claude Opus 4.6 Anthropic

58.2

Rank #20 Confirmed

GPT-5.3 Chat OpenAI

42.8

Rank #109 Confirmed

Summary

  • They share 18 benchmarks with published results for both. Claude Opus 4.6 scores higher in 8 categories and GPT-5.3 Chat in 0 categories; 8 gaps are clear of the uncertainty.
  • The widest gap is in reasoning, where Claude Opus 4.6 leads 57.8 to 28.5.
  • GPT-5.3 Chat is cheaper at $1.75 / $14 per million input/output tokens, against $5 / $25 for Claude Opus 4.6.
  • Claude Opus 4.6 accepts more context: 1M tokens versus 128K.

Side by side

Claude Opus 4.6 and GPT-5.3 Chat specifications
Claude Opus 4.6GPT-5.3 Chat
ProviderAnthropicOpenAI
Noometry Index58.242.8
Released2026-02-042026-03-03
WeightsProprietaryProprietary
Context window1M128K
Max output128K16K
Input $ / M tokens$5$1.75
Output $ / M tokens$25$14
Results tracked6818

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Category by category

Coding Claude Opus 4.6 leads

Claude Opus 4.6: 57.2 (#20), GPT-5.3 Chat: 41.4 (#124)

Coding benchmarks
BenchmarkClaude Opus 4.6GPT-5.3 Chat
LMArena Coding15361408
SWE-bench Verified78.7%—
FrontierCode26.6%—
SWE-bench Verified (bash only)75.6%—
LMArena WebDev1547—
SWE-bench Multilingual72%—
GSO41.2%—
WeirdML78%—
ALE-Bench996.5—
AlgoTune1.47—

Agentic & Tool Use Not comparable

Claude Opus 4.6: 51.1 (#4), GPT-5.3 Chat: —

Agentic & Tool Use benchmarks
BenchmarkClaude Opus 4.6GPT-5.3 Chat
Terminal-Bench79.8%—
APEX-Agents46.3%—
Remote Labor Index4.2%—
τ²-bench Banking27.3%—
Cybench93%—
DeepResearch Bench55.3%—
GBAEval44.1%—
LMArena Search1253—
METR Time Horizons78.9%—
Vending-Bench 28,018—

Reasoning Claude Opus 4.6 leads

Claude Opus 4.6: 57.8 (#23), GPT-5.3 Chat: 28.5 (#102)

Reasoning benchmarks
BenchmarkClaude Opus 4.6GPT-5.3 Chat
LMArena Hard Prompts15271399
ARC-AGI-269.2%—
SimpleBench67.6%—
Kagi LLM Benchmark83.6%—
NYT Connections (extended)92.1%—
ARC-AGI-194%—
Chess Puzzles17%—
EnigmaEval7.6%—
Thematic Generalization80.6%—
EBR-Bench12.7%—
Mystery Game Puzzles25%—
DTBench91.2%—
LMCA55.8%—
Epoch Capabilities Index155.24—
ForecastBench60—

Math Claude Opus 4.6 leads

Claude Opus 4.6: 63.0 (#31), GPT-5.3 Chat: 38.2 (#142)

Knowledge Claude Opus 4.6 leads

Claude Opus 4.6: 61.9 (#26), GPT-5.3 Chat: 38.8 (#140)

Knowledge benchmarks
BenchmarkClaude Opus 4.6GPT-5.3 Chat
LMArena Expert15461397
GPQA Diamond90.5%—
Humanity's Last Exam34.4%—
SimpleQA Verified47%—
Vectara Hallucination Rate12.2%—

Multimodal Not comparable

Claude Opus 4.6: 37.3 (#74), GPT-5.3 Chat: —

Multimodal benchmarks
BenchmarkClaude Opus 4.6GPT-5.3 Chat
LMArena Vision1316—
Furniture Assembly28.3%—
LMArena Document1507—

Multilingual Claude Opus 4.6 leads

Claude Opus 4.6: 57.9 (#6), GPT-5.3 Chat: 50.3 (#124)

Multilingual benchmarks
BenchmarkClaude Opus 4.6GPT-5.3 Chat
LMArena Non-English14891382
LMArena Chinese15511432
LMArena French15131397
LMArena German15021384
LMArena Japanese14841352
LMArena Korean14641346
LMArena Russian14971400
LMArena Spanish15101371

Instruction Following Claude Opus 4.6 leads

Claude Opus 4.6: 79.5 (#4), GPT-5.3 Chat: 72.8 (#129)

Instruction Following benchmarks
BenchmarkClaude Opus 4.6GPT-5.3 Chat
LMArena Instruction Following15231378

Long Context Claude Opus 4.6 leads

Claude Opus 4.6: 48.1 (#13), GPT-5.3 Chat: 42.6 (#120)

Long Context benchmarks
BenchmarkClaude Opus 4.6GPT-5.3 Chat
LMArena Longer Query15201396
CL-bench20.7%—
CL-bench Life17%—

Writing & Preference Claude Opus 4.6 leads

Claude Opus 4.6: 73.5 (#10), GPT-5.3 Chat: 63.1 (#68)

Writing & Preference benchmarks
BenchmarkClaude Opus 4.6GPT-5.3 Chat
LMArena Text15031389
LMArena Creative Writing15051355
EQ-Bench Creative Writing18091690
LMArena Multi-Turn15131412
EQ-Bench 41223—

Frequently asked questions

Is Claude Opus 4.6 better than GPT-5.3 Chat?

Claude Opus 4.6 is the stronger model overall, scoring 58.2 to 42.8 on the Noometry Index. GPT-5.3 Chat costs 2.1× less per token, which makes it the better buy when Claude Opus 4.6's lead doesn't matter for your workload.

Which is cheaper, Claude Opus 4.6 or GPT-5.3 Chat?

GPT-5.3 Chat is cheaper. It lists at $1.75 per million input tokens and $14 per million output tokens; Claude Opus 4.6 lists at $5 and $25.

Is Claude Opus 4.6 or GPT-5.3 Chat better for coding?

Claude Opus 4.6 scores higher on coding benchmarks: 57.2 versus 41.4 in the Noometry coding category.

Which has the bigger context window?

Claude Opus 4.6 does, with 1M tokens against 128K.

How many benchmarks do Claude Opus 4.6 and GPT-5.3 Chat share?

18 benchmarks have published results for both models. Claude Opus 4.6 has 68 scored results on Noometry and GPT-5.3 Chat has 18.

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