Model comparison

GPT-5.5 vs Inkling

GPT-5.5 is the stronger model overall, scoring 63.4 to 44.1 on the Noometry Index. Inkling costs 4.4× less per token, which makes it the better buy when GPT-5.5's lead doesn't matter for your workload.

Last verified . 40 shared benchmarks.

GPT-5.5 OpenAI

63.4

Rank #9 Confirmed

Inkling Thinking Machines Lab

44.1

Rank #80 Confirmed

Summary

  • They share 40 benchmarks with published results for both. GPT-5.5 scores higher in 9 categories and Inkling in 0 categories; 9 gaps are clear of the uncertainty.
  • The widest gap is in math, where GPT-5.5 leads 81.7 to 31.3.
  • The biggest single-benchmark swing is FrontierMath Tier 4: 72.5% for GPT-5.5 and 4.9% for Inkling.
  • Inkling is cheaper at $1.87 / $4.68 per million input/output tokens, against $5 / $30 for GPT-5.5.
  • GPT-5.5 accepts more context: 1.05M tokens versus 66K.
  • Inkling has downloadable open weights; the other is API-only.

Side by side

GPT-5.5 and Inkling specifications
GPT-5.5Inkling
ProviderOpenAIThinking Machines Lab
Noometry Index63.444.1
Released2026-04-232026-07-15
WeightsProprietaryOpen
Context window1.05M66K
Max output128K66K
Input $ / M tokens$5$1.87
Output $ / M tokens$30$4.68
Results tracked7141

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

Category by category

Coding GPT-5.5 leads

GPT-5.5: 58.2 (#17), Inkling: 34.5 (#234)

Coding benchmarks
BenchmarkGPT-5.5Inkling
FrontierCode43%14%
LMArena WebDev15131413
SciCode56.1%47%
WeirdML84.9%32.3%
LMArena Coding14941464
ALE-Bench1,943946
SWE-bench Verified80.6%—
DeepSWE67%—
FrontierSWE—4.1%
GSO40.2%—
MirrorCode10%—

Agentic & Tool Use GPT-5.5 leads

GPT-5.5: 50.7 (#6), Inkling: 29.6 (#85)

Agentic & Tool Use benchmarks
BenchmarkGPT-5.5Inkling
APEX-Agents55.1%33.8%
τ²-bench Banking44.6%25%
Terminal-Bench84.7%—
OSWorld 2.013%—
Remote Labor Index6.3%—
DeepResearch Bench54%—
PostTrainBench27.2%—
ExploitBench47.4%—
GBAEval53.2%—
GDP.pdf26%—
LMArena Search1242—
Vending-Bench 27,524—

Reasoning GPT-5.5 leads

GPT-5.5: 72.8 (#11), Inkling: 40.4 (#56)

Reasoning benchmarks
BenchmarkGPT-5.5Inkling
ARC-AGI-285%36.5%
SimpleBench69%50%
ARC-AGI-195%79.5%
CritPt27.1%5.4%
Chess Puzzles54%21%
LMArena Hard Prompts14891451
DTBench96%87.5%
LMCA54.3%37.6%
Epoch Capabilities Index159.1148.54
Kagi LLM Benchmark88.8%—
NYT Connections (extended)96.2%—
EBR-Bench34.3%—
Mystery Game Puzzles56%—
Surface Evolver Bench88.1%—
Bench to the Future 30.14—
ForecastBench60.6—

Math GPT-5.5 leads

GPT-5.5: 81.7 (#11), Inkling: 31.3 (#225)

Knowledge GPT-5.5 leads

GPT-5.5: 64.4 (#17), Inkling: 55.1 (#49)

Knowledge benchmarks
BenchmarkGPT-5.5Inkling
GPQA Diamond94%88.3%
SimpleQA Verified63%40.3%
LMArena Expert15081465
Vectara Hallucination Rate9.3%—

Multimodal Not comparable

GPT-5.5: 46.9 (#12), Inkling: —

Multimodal benchmarks
BenchmarkGPT-5.5Inkling
LMArena Vision1297—
Blueprint-Bench 236.2%—
Furniture Assembly44.2%—
LMArena Document1486—

Multilingual GPT-5.5 leads

GPT-5.5: 56.4 (#20), Inkling: 54.0 (#52)

Multilingual benchmarks
BenchmarkGPT-5.5Inkling
LMArena Non-English14671434
LMArena Chinese15331490
LMArena French14861458
LMArena German14801446
LMArena Japanese14981429
LMArena Korean14601404
LMArena Russian14731429
LMArena Spanish14681448

Instruction Following GPT-5.5 leads

GPT-5.5: 77.5 (#18), Inkling: 75.1 (#71)

Instruction Following benchmarks
BenchmarkGPT-5.5Inkling
LMArena Instruction Following14791426

Long Context GPT-5.5 leads

GPT-5.5: 48.3 (#12), Inkling: 43.8 (#86)

Long Context benchmarks
BenchmarkGPT-5.5Inkling
LMArena Longer Query14841434
CL-bench Life22.2%—

Writing & Preference GPT-5.5 leads

GPT-5.5: 72.7 (#13), Inkling: 65.2 (#51)

Writing & Preference benchmarks
BenchmarkGPT-5.5Inkling
LMArena Text14721441
LMArena Creative Writing14551387
EQ-Bench Creative Writing18441611
EQ-Bench 413151226
LMArena Multi-Turn14761436

Frequently asked questions

Is GPT-5.5 better than Inkling?

GPT-5.5 is the stronger model overall, scoring 63.4 to 44.1 on the Noometry Index. Inkling costs 4.4× less per token, which makes it the better buy when GPT-5.5's lead doesn't matter for your workload.

Which is cheaper, GPT-5.5 or Inkling?

Inkling is cheaper. It lists at $1.87 per million input tokens and $4.68 per million output tokens; GPT-5.5 lists at $5 and $30.

Is GPT-5.5 or Inkling better for coding?

GPT-5.5 scores higher on coding benchmarks: 58.2 versus 34.5 in the Noometry coding category.

Which has the bigger context window?

GPT-5.5 does, with 1.05M tokens against 66K.

How many benchmarks do GPT-5.5 and Inkling share?

40 benchmarks have published results for both models. GPT-5.5 has 71 scored results on Noometry and Inkling has 41.

Related comparisons

Go deeper