Noometry

Model comparison

Claude Sonnet 5 vs GPT-5.3 Chat

Claude Sonnet 5 is the stronger model overall, scoring 54.6 to 42.8 on the Noometry Index.

Last verified . 18 shared benchmarks.

Claude Sonnet 5 Anthropic

54.6

Rank #29 Confirmed

GPT-5.3 Chat OpenAI

42.8

Rank #109 Confirmed

Summary

  • They share 18 benchmarks with published results for both. Claude Sonnet 5 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 math, where Claude Sonnet 5 leads 66.2 to 38.2.
  • Claude Sonnet 5 is cheaper at $2 / $10 per million input/output tokens, against $1.75 / $14 for GPT-5.3 Chat.
  • Claude Sonnet 5 accepts more context: 1M tokens versus 128K.

Side by side

Claude Sonnet 5GPT-5.3 Chat
ProviderAnthropicOpenAI
Noometry Index54.642.8
Released2026-06-292026-03-03
WeightsProprietaryProprietary
Context window1M128K
Max output128K16K
Input $ / M tokens$2$1.75
Output $ / M tokens$10$14
Results tracked5118

Sponsored placements are available on pages like this one. Advertise on Noometry

Category by category

Coding Claude Sonnet 5 leads

Claude Sonnet 5: 55.5 (#26), GPT-5.3 Chat: 41.4 (#124)

BenchmarkClaude Sonnet 5GPT-5.3 Chat
LMArena Coding14831408
DeepSWE53.8%—
FrontierCode42.7%—
CursorBench34.1%—
LMArena WebDev1541—
SciCode54.3%—
GSO37.3%—
WeirdML68.8%—
ALE-Bench1,463—

Agentic & Tool Use Not comparable

Claude Sonnet 5: 42.8 (#18), GPT-5.3 Chat: —

BenchmarkClaude Sonnet 5GPT-5.3 Chat
APEX-Agents54.5%—
GBAEval65.3%—
LMArena Search1194—
Vending-Bench 26,378—

Reasoning Claude Sonnet 5 leads

Claude Sonnet 5: 49.1 (#39), GPT-5.3 Chat: 28.5 (#102)

BenchmarkClaude Sonnet 5GPT-5.3 Chat
LMArena Hard Prompts14611399
SimpleBench60.6%—
NYT Connections (extended)75.1%—
CritPt16.9%—
Chess Puzzles35%—
Mystery Game Puzzles35%—
DTBench92.5%—
LMCA50%—
Surface Evolver Bench60%—
Bench to the Future 30.14—
Epoch Capabilities Index156.21—
ForecastBench61.1—

Math Claude Sonnet 5 leads

Claude Sonnet 5: 66.2 (#27), GPT-5.3 Chat: 38.2 (#142)

BenchmarkClaude Sonnet 5GPT-5.3 Chat
LMArena Math14671389
FrontierMath (Tiers 1-3)65.6%—
FrontierMath Tier 429.3%—
OTIS Mock AIME 2024-202594.7%—
ProofBench77%—

Knowledge Claude Sonnet 5 leads

Claude Sonnet 5: 55.6 (#47), GPT-5.3 Chat: 38.8 (#140)

BenchmarkClaude Sonnet 5GPT-5.3 Chat
LMArena Expert14901397
GPQA Diamond90.5%—
SimpleQA Verified33.7%—

Multimodal Not comparable

Claude Sonnet 5: 42.4 (#31), GPT-5.3 Chat: —

BenchmarkClaude Sonnet 5GPT-5.3 Chat
LMArena Vision1274—
Blueprint-Bench 224.9%—
LMArena Document1466—

Multilingual Claude Sonnet 5 leads

Claude Sonnet 5: 53.8 (#55), GPT-5.3 Chat: 50.3 (#124)

BenchmarkClaude Sonnet 5GPT-5.3 Chat
LMArena Non-English14311382
LMArena Chinese14771432
LMArena French14601397
LMArena German14401384
LMArena Japanese14221352
LMArena Korean14111346
LMArena Russian14511400
LMArena Spanish14371371

Instruction Following Claude Sonnet 5 leads

Claude Sonnet 5: 76.3 (#41), GPT-5.3 Chat: 72.8 (#129)

BenchmarkClaude Sonnet 5GPT-5.3 Chat
LMArena Instruction Following14521378

Long Context Claude Sonnet 5 leads

Claude Sonnet 5: 44.8 (#55), GPT-5.3 Chat: 42.6 (#120)

BenchmarkClaude Sonnet 5GPT-5.3 Chat
LMArena Longer Query14631396

Writing & Preference Claude Sonnet 5 leads

Claude Sonnet 5: 69.2 (#25), GPT-5.3 Chat: 63.1 (#68)

BenchmarkClaude Sonnet 5GPT-5.3 Chat
LMArena Text14421389
LMArena Creative Writing14161355
EQ-Bench Creative Writing17941690
LMArena Multi-Turn14541412
EQ-Bench 41236—

Frequently asked questions

Is Claude Sonnet 5 better than GPT-5.3 Chat?

Claude Sonnet 5 is the stronger model overall, scoring 54.6 to 42.8 on the Noometry Index.

Which is cheaper, Claude Sonnet 5 or GPT-5.3 Chat?

Claude Sonnet 5 is cheaper. It lists at $2 per million input tokens and $10 per million output tokens; GPT-5.3 Chat lists at $1.75 and $14.

Is Claude Sonnet 5 or GPT-5.3 Chat better for coding?

Claude Sonnet 5 scores higher on coding benchmarks: 55.5 versus 41.4 in the Noometry coding category.

Which has the bigger context window?

Claude Sonnet 5 does, with 1M tokens against 128K.

How many benchmarks do Claude Sonnet 5 and GPT-5.3 Chat share?

18 benchmarks have published results for both models. Claude Sonnet 5 has 51 scored results on Noometry and GPT-5.3 Chat has 18.

Related comparisons

Go deeper