Model comparison

GPT-5.6 Sol vs GPT-6.1 Sol

GPT-5.6 Sol and GPT-6.1 Sol score almost the same on the Noometry Index (65.0 vs 65.6), so choose on price, context window or the category you care about most.

Last verified . 34 shared benchmarks.

GPT-5.6 Sol OpenAI

65.0

Rank #7 Confirmed

GPT-6.1 Sol OpenAI

65.6

Rank #6 Confirmed

Summary

  • They share 34 benchmarks with published results for both. GPT-5.6 Sol scores higher in 6 categories and GPT-6.1 Sol in 4 categories; 7 gaps are clear of the uncertainty.
  • The widest gap is in agentic & tool use, where GPT-5.6 Sol leads 50.3 to 39.6.
  • The biggest single-benchmark swing is Furniture Assembly: 56.7% for GPT-5.6 Sol and 80% for GPT-6.1 Sol.
  • GPT-6.1 Sol is cheaper at $2 / $10 per million input/output tokens, against $4 / $20 for GPT-5.6 Sol.

Side by side

GPT-5.6 Sol and GPT-6.1 Sol specifications
GPT-5.6 SolGPT-6.1 Sol
ProviderOpenAIOpenAI
Noometry Index65.065.6
Released2026-07-092026-09-29
WeightsProprietaryProprietary
Context window1.05M1.05M
Max output128K128K
Input $ / M tokens$4$2
Output $ / M tokens$20$10
Results tracked6534

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

Category by category

Coding GPT-5.6 Sol leads

GPT-5.6 Sol: 65.1 (#7), GPT-6.1 Sol: 63.2 (#8)

Coding benchmarks
BenchmarkGPT-5.6 SolGPT-6.1 Sol
DeepSWE72.7%75.2%
FrontierCode47.5%50.2%
LMArena WebDev16181755
SciCode57.1%55.8%
LMArena Coding14981487
CursorBench41.7%—
FrontierSWE32.2%—
GSO76.5%—
WeirdML89.4%—
MirrorCode20%—
ALE-Bench2,177—

Agentic & Tool Use GPT-5.6 Sol leads

GPT-5.6 Sol: 50.3 (#7), GPT-6.1 Sol: 39.6 (#26)

Agentic & Tool Use benchmarks
BenchmarkGPT-5.6 SolGPT-6.1 Sol
APEX-Agents51.4%60%
GDP.pdf30.7%32%
OSWorld 2.027.3%—
τ²-bench Banking46.9%—
PostTrainBench36.2%—
BALROG60%—
GBAEval52.6%—
LMArena Search1257—
Vending-Bench 29,619—

Reasoning GPT-6.1 Sol leads

GPT-5.6 Sol: 74.8 (#8), GPT-6.1 Sol: 81.9 (#2)

Reasoning benchmarks
BenchmarkGPT-5.6 SolGPT-6.1 Sol
ARC-AGI-292.5%94.2%
NYT Connections (extended)93.8%95.5%
ARC-AGI-197.5%98.5%
CritPt32.3%31.7%
Chess Puzzles64%61%
EBR-Bench44.8%54.3%
LMArena Hard Prompts14841466
Mystery Game Puzzles58%80%
Epoch Capabilities Index161.66166.09
SimpleBench71.7%—
Kagi LLM Benchmark67%—
EnigmaEval37.1%—
DTBench96%—
LMCA59.2%—
Surface Evolver Bench93.1%—
Bench to the Future 30.14—

Math GPT-6.1 Sol leads

GPT-5.6 Sol: 85.6 (#9), GPT-6.1 Sol: 93.7 (#1)

Math benchmarks
BenchmarkGPT-5.6 SolGPT-6.1 Sol
FrontierMath (Tiers 1-3)89.1%93.7%
FrontierMath Tier 482.9%100%
OTIS Mock AIME 2024-2025100%100%
ProofBench83%99%
LMArena Math14741464
FrontierMath Erdős0%—

Knowledge GPT-6.1 Sol leads

GPT-5.6 Sol: 64.3 (#18), GPT-6.1 Sol: 71.8 (#4)

Knowledge benchmarks
BenchmarkGPT-5.6 SolGPT-6.1 Sol
GPQA Diamond93.5%95.4%
SimpleQA Verified69.7%73.9%
LMArena Expert15161502
Vectara Hallucination Rate12.4%—

Multimodal GPT-6.1 Sol leads

GPT-5.6 Sol: 48.6 (#9), GPT-6.1 Sol: 52.7 (#5)

Multimodal benchmarks
BenchmarkGPT-5.6 SolGPT-6.1 Sol
LMArena Vision12811288
Furniture Assembly56.7%80%
Blueprint-Bench 233.6%—
LMArena Document1483—

Multilingual Too close to call

GPT-5.6 Sol: 55.3 (#32), GPT-6.1 Sol: 54.3 (#46)

Multilingual benchmarks
BenchmarkGPT-5.6 SolGPT-6.1 Sol
LMArena Non-English14521438
LMArena Chinese15271477
LMArena Russian14681455
LMArena French1477—
LMArena German1476—
LMArena Japanese1471—
LMArena Korean1442—
LMArena Spanish1441—

Instruction Following Too close to call

GPT-5.6 Sol: 77.7 (#16), GPT-6.1 Sol: 77.0 (#29)

Instruction Following benchmarks
BenchmarkGPT-5.6 SolGPT-6.1 Sol
LMArena Instruction Following14821468

Long Context Too close to call

GPT-5.6 Sol: 45.4 (#42), GPT-6.1 Sol: 44.9 (#54)

Long Context benchmarks
BenchmarkGPT-5.6 SolGPT-6.1 Sol
LMArena Longer Query14801465

Writing & Preference GPT-5.6 Sol leads

GPT-5.6 Sol: 73.3 (#12), GPT-6.1 Sol: 63.6 (#63)

Writing & Preference benchmarks
BenchmarkGPT-5.6 SolGPT-6.1 Sol
LMArena Text14571447
LMArena Creative Writing14481432
LMArena Multi-Turn14601449
EQ-Bench Creative Writing1972—
EQ-Bench 41250—

Frequently asked questions

Is GPT-5.6 Sol better than GPT-6.1 Sol?

GPT-5.6 Sol and GPT-6.1 Sol score almost the same on the Noometry Index (65.0 vs 65.6), so choose on price, context window or the category you care about most.

Which is cheaper, GPT-5.6 Sol or GPT-6.1 Sol?

GPT-6.1 Sol is cheaper. It lists at $2 per million input tokens and $10 per million output tokens; GPT-5.6 Sol lists at $4 and $20.

Is GPT-5.6 Sol or GPT-6.1 Sol better for coding?

GPT-5.6 Sol scores higher on coding benchmarks: 65.1 versus 63.2 in the Noometry coding category.

Which has the bigger context window?

Both accept 1.05M tokens.

How many benchmarks do GPT-5.6 Sol and GPT-6.1 Sol share?

34 benchmarks have published results for both models. GPT-5.6 Sol has 65 scored results on Noometry and GPT-6.1 Sol has 34.

Related comparisons

Go deeper