Model comparison

GPT-5.6 Sol vs Hy4 preview

GPT-5.6 Sol is the stronger model overall, scoring 64.4 to 44.6 on the Noometry Index. Hy4 preview costs 6.4× less per token, which makes it the better buy when GPT-5.6 Sol's lead doesn't matter for your workload.

Last verified . 3 shared benchmarks.

GPT-5.6 Sol OpenAI

64.4

Rank #6 Confirmed

Hy4 preview Tencent

44.6

Rank #73 Reported

Summary

  • They share 3 benchmarks with published results for both. GPT-5.6 Sol scores higher in 3 categories and Hy4 preview in 0 categories; 3 gaps are clear of the uncertainty.
  • The widest gap is in reasoning, where GPT-5.6 Sol leads 74.7 to 30.6.
  • The biggest single-benchmark swing is NYT Connections (extended): 93.8% for GPT-5.6 Sol and 68.2% for Hy4 preview.
  • Hy4 preview is cheaper at $0.83 / $2.50 per million input/output tokens, against $4 / $20 for GPT-5.6 Sol.
  • GPT-5.6 Sol accepts more context: 1.05M tokens versus 1.05M.
  • Hy4 preview has downloadable open weights; the other is API-only.

Side by side

GPT-5.6 Sol and Hy4 preview specifications
GPT-5.6 SolHy4 preview
ProviderOpenAITencent
Noometry Index64.444.6
Released2026-07-092026-08-28
WeightsProprietaryOpen
Context window1.05M1.05M
Max output128K64K
Input $ / M tokens$4$0.83
Output $ / M tokens$20$2.50
Results tracked643

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: 61.1 (#7), Hy4 preview: 51.4 (#36)

Coding benchmarks
BenchmarkGPT-5.6 SolHy4 preview
LMArena WebDev16191633
DeepSWE72.7%—
FrontierCode47.5%—
CursorBench41.7%—
FrontierSWE32.2%—
SciCode57.1%—
WeirdML89.4%—
LMArena Coding1493—
MirrorCode20%—
ALE-Bench2,177—

Agentic & Tool Use Not comparable

GPT-5.6 Sol: 50.2 (#7), Hy4 preview: —

Agentic & Tool Use benchmarks
BenchmarkGPT-5.6 SolHy4 preview
APEX-Agents51.4%—
OSWorld 2.027.3%—
τ²-bench Banking46.9%—
PostTrainBench36.2%—
BALROG60%—
GBAEval52.6%—
GDP.pdf30.7%—
LMArena Search1257—
Vending-Bench 29,619—

Reasoning GPT-5.6 Sol leads

GPT-5.6 Sol: 74.7 (#6), Hy4 preview: 30.6 (#75)

Reasoning benchmarks
BenchmarkGPT-5.6 SolHy4 preview
NYT Connections (extended)93.8%68.2%
ARC-AGI-292.5%—
SimpleBench71.7%—
Kagi LLM Benchmark67%—
ARC-AGI-197.5%—
CritPt32.3%—
Chess Puzzles64%—
EnigmaEval37.1%—
EBR-Bench44.8%—
LMArena Hard Prompts1481—
Mystery Game Puzzles58%—
DTBench96%—
LMCA59.2%—
Surface Evolver Bench93.1%—
Bench to the Future 30.14—
Epoch Capabilities Index161.99—

Math GPT-5.6 Sol leads

GPT-5.6 Sol: 85.5 (#7), Hy4 preview: 54.5 (#37)

Math benchmarks
BenchmarkGPT-5.6 SolHy4 preview
ProofBench83%75%
FrontierMath (Tiers 1-3)89.1%—
FrontierMath Tier 482.9%—
OTIS Mock AIME 2024-2025100%—
LMArena Math1472—
FrontierMath Erdős0%—

Knowledge Not comparable

GPT-5.6 Sol: 64.3 (#16), Hy4 preview: —

Knowledge benchmarks
BenchmarkGPT-5.6 SolHy4 preview
GPQA Diamond93.5%—
SimpleQA Verified69.7%—
Vectara Hallucination Rate12.4%—
LMArena Expert1517—

Multimodal Not comparable

GPT-5.6 Sol: 48.9 (#8), Hy4 preview: —

Multimodal benchmarks
BenchmarkGPT-5.6 SolHy4 preview
LMArena Vision1281—
Blueprint-Bench 233.6%—
Furniture Assembly56.7%—
LMArena Document1483—

Multilingual Not comparable

GPT-5.6 Sol: 55.4 (#32), Hy4 preview: —

Multilingual benchmarks
BenchmarkGPT-5.6 SolHy4 preview
LMArena Non-English1450—
LMArena Chinese1523—
LMArena French1475—
LMArena German1476—
LMArena Japanese1475—
LMArena Korean1434—
LMArena Russian1466—
LMArena Spanish1449—

Instruction Following Not comparable

GPT-5.6 Sol: 77.8 (#16), Hy4 preview: —

Instruction Following benchmarks
BenchmarkGPT-5.6 SolHy4 preview
LMArena Instruction Following1480—

Long Context Not comparable

GPT-5.6 Sol: 45.3 (#42), Hy4 preview: —

Long Context benchmarks
BenchmarkGPT-5.6 SolHy4 preview
LMArena Longer Query1479—

Writing & Preference Not comparable

GPT-5.6 Sol: 73.5 (#12), Hy4 preview: —

Writing & Preference benchmarks
BenchmarkGPT-5.6 SolHy4 preview
LMArena Text1456—
LMArena Creative Writing1450—
EQ-Bench Creative Writing1972—
EQ-Bench 41250—
LMArena Multi-Turn1456—

Frequently asked questions

Is GPT-5.6 Sol better than Hy4 preview?

GPT-5.6 Sol is the stronger model overall, scoring 64.4 to 44.6 on the Noometry Index. Hy4 preview costs 6.4× less per token, which makes it the better buy when GPT-5.6 Sol's lead doesn't matter for your workload.

Which is cheaper, GPT-5.6 Sol or Hy4 preview?

Hy4 preview is cheaper. It lists at $0.83 per million input tokens and $2.50 per million output tokens; GPT-5.6 Sol lists at $4 and $20.

Is GPT-5.6 Sol or Hy4 preview better for coding?

GPT-5.6 Sol scores higher on coding benchmarks: 61.1 versus 51.4 in the Noometry coding category.

Which has the bigger context window?

GPT-5.6 Sol does, with 1.05M tokens against 1.05M.

How many benchmarks do GPT-5.6 Sol and Hy4 preview share?

3 benchmarks have published results for both models. GPT-5.6 Sol has 64 scored results on Noometry and Hy4 preview has 3.

Related comparisons

Go deeper