Noometry

Model comparison

Claude Opus 4.6 vs GPT-5.6 Terra

Claude Opus 4.6 and GPT-5.6 Terra score almost the same on the Noometry Index (58.2 vs 59.2), so choose on price, context window or the category you care about most.

Last verified . 44 shared benchmarks.

Claude Opus 4.6 Anthropic

58.2

Rank #20 Confirmed

GPT-5.6 Terra OpenAI

59.2

Rank #17 Confirmed

Summary

  • They share 44 benchmarks with published results for both. Claude Opus 4.6 scores higher in 6 categories and GPT-5.6 Terra in 4 categories; 8 gaps are clear of the uncertainty.
  • The widest gap is in math, where GPT-5.6 Terra leads 81.6 to 63.0.
  • The biggest single-benchmark swing is FrontierMath Tier 4: 26.8% for Claude Opus 4.6 and 70.7% for GPT-5.6 Terra.
  • GPT-5.6 Terra is cheaper at $2 / $12 per million input/output tokens, against $5 / $25 for Claude Opus 4.6.
  • GPT-5.6 Terra accepts more context: 1.05M tokens versus 1M.

Side by side

Claude Opus 4.6GPT-5.6 Terra
ProviderAnthropicOpenAI
Noometry Index58.259.2
Released2026-02-042026-07-09
WeightsProprietaryProprietary
Context window1M1.05M
Max output128K128K
Input $ / M tokens$5$2
Output $ / M tokens$25$12
Results tracked6852

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

Category by category

Coding Too close to call

Claude Opus 4.6: 57.2 (#20), GPT-5.6 Terra: 57.7 (#19)

BenchmarkClaude Opus 4.6GPT-5.6 Terra
FrontierCode26.6%41.3%
LMArena WebDev15471522
WeirdML78%78.3%
LMArena Coding15361484
ALE-Bench996.51,951
SWE-bench Verified78.7%—
DeepSWE—69.6%
SWE-bench Verified (bash only)75.6%—
CursorBench—41.3%
SWE-bench Multilingual72%—
SciCode—55%
GSO41.2%—
AlgoTune1.47—

Agentic & Tool Use Claude Opus 4.6 leads

Claude Opus 4.6: 51.1 (#4), GPT-5.6 Terra: 40.1 (#25)

BenchmarkClaude Opus 4.6GPT-5.6 Terra
APEX-Agents46.3%58.2%
Vending-Bench 28,0187,343
Terminal-Bench79.8%—
Remote Labor Index4.2%—
τ²-bench Banking27.3%—
Cybench93%—
DeepResearch Bench55.3%—
BALROG—53.2%
GBAEval44.1%—
GDP.pdf—24.7%
LMArena Search1253—
METR Time Horizons78.9%—

Reasoning GPT-5.6 Terra leads

Claude Opus 4.6: 57.8 (#23), GPT-5.6 Terra: 60.7 (#21)

BenchmarkClaude Opus 4.6GPT-5.6 Terra
ARC-AGI-269.2%83.9%
SimpleBench67.6%48.9%
Kagi LLM Benchmark83.6%51.3%
NYT Connections (extended)92.1%78.4%
ARC-AGI-194%96.5%
Chess Puzzles17%54%
LMArena Hard Prompts15271468
Mystery Game Puzzles25%35%
DTBench91.2%93.3%
LMCA55.8%55%
Epoch Capabilities Index155.24159.62
CritPt—30%
EnigmaEval7.6%—
Thematic Generalization80.6%—
EBR-Bench12.7%—
Surface Evolver Bench—83.8%
ForecastBench60—

Math GPT-5.6 Terra leads

Claude Opus 4.6: 63.0 (#31), GPT-5.6 Terra: 81.6 (#12)

BenchmarkClaude Opus 4.6GPT-5.6 Terra
FrontierMath (Tiers 1-3)66%86%
FrontierMath Tier 426.8%70.7%
OTIS Mock AIME 2024-202594.4%99.7%
ProofBench50%74%
LMArena Math15191466
MathArena Final-Answer Competitions78.5%—
FrontierMath (Feb 2025 set)40.7%—
FrontierMath Tier 4 (v1)22.9%—

Knowledge Too close to call

Claude Opus 4.6: 61.9 (#26), GPT-5.6 Terra: 61.2 (#30)

BenchmarkClaude Opus 4.6GPT-5.6 Terra
GPQA Diamond90.5%93.3%
SimpleQA Verified47%43.2%
LMArena Expert15461492
Humanity's Last Exam34.4%—
Vectara Hallucination Rate12.2%—

Multimodal GPT-5.6 Terra leads

Claude Opus 4.6: 37.3 (#74), GPT-5.6 Terra: 47.3 (#11)

BenchmarkClaude Opus 4.6GPT-5.6 Terra
LMArena Vision13161271
Furniture Assembly28.3%54.2%
LMArena Document15071472
Blueprint-Bench 2—30.8%

Multilingual Claude Opus 4.6 leads

Claude Opus 4.6: 57.9 (#6), GPT-5.6 Terra: 54.4 (#44)

BenchmarkClaude Opus 4.6GPT-5.6 Terra
LMArena Non-English14891439
LMArena Chinese15511513
LMArena French15131471
LMArena German15021460
LMArena Japanese14841457
LMArena Korean14641425
LMArena Russian14971450
LMArena Spanish15101448

Instruction Following Claude Opus 4.6 leads

Claude Opus 4.6: 79.5 (#4), GPT-5.6 Terra: 76.4 (#40)

BenchmarkClaude Opus 4.6GPT-5.6 Terra
LMArena Instruction Following15231454

Long Context Claude Opus 4.6 leads

Claude Opus 4.6: 48.1 (#13), GPT-5.6 Terra: 44.4 (#68)

BenchmarkClaude Opus 4.6GPT-5.6 Terra
LMArena Longer Query15201451
CL-bench20.7%—
CL-bench Life17%—

Writing & Preference Claude Opus 4.6 leads

Claude Opus 4.6: 73.5 (#10), GPT-5.6 Terra: 70.2 (#23)

BenchmarkClaude Opus 4.6GPT-5.6 Terra
LMArena Text15031447
LMArena Creative Writing15051410
EQ-Bench Creative Writing18091855
EQ-Bench 412231234
LMArena Multi-Turn15131449

Frequently asked questions

Is Claude Opus 4.6 better than GPT-5.6 Terra?

Claude Opus 4.6 and GPT-5.6 Terra score almost the same on the Noometry Index (58.2 vs 59.2), so choose on price, context window or the category you care about most.

Which is cheaper, Claude Opus 4.6 or GPT-5.6 Terra?

GPT-5.6 Terra is cheaper. It lists at $2 per million input tokens and $12 per million output tokens; Claude Opus 4.6 lists at $5 and $25.

Is Claude Opus 4.6 or GPT-5.6 Terra better for coding?

They score almost the same on coding (57.2 vs 57.7); test both on your own repository before choosing.

Which has the bigger context window?

GPT-5.6 Terra does, with 1.05M tokens against 1M.

How many benchmarks do Claude Opus 4.6 and GPT-5.6 Terra share?

44 benchmarks have published results for both models. Claude Opus 4.6 has 68 scored results on Noometry and GPT-5.6 Terra has 52.

Related comparisons

Go deeper