Model comparison

Claude Opus 4.5 vs Inkling

Claude Opus 4.5 is the stronger model overall, scoring 50.5 to 44.1 on the Noometry Index. Inkling costs 3.9× less per token, which makes it the better buy when Claude Opus 4.5's lead doesn't matter for your workload.

Last verified . 35 shared benchmarks.

Claude Opus 4.5 Anthropic

50.5

Rank #47 Confirmed

Inkling Thinking Machines Lab

44.1

Rank #80 Confirmed

Summary

  • They share 35 benchmarks with published results for both. Claude Opus 4.5 scores higher in 9 categories and Inkling in 0 categories; 8 gaps are clear of the uncertainty.
  • The widest gap is in coding, where Claude Opus 4.5 leads 54.8 to 34.5.
  • The biggest single-benchmark swing is ProofBench: 36% for Claude Opus 4.5 and 0% for Inkling.
  • Inkling is cheaper at $1.87 / $4.68 per million input/output tokens, against $5 / $25 for Claude Opus 4.5.
  • Claude Opus 4.5 accepts more context: 200K tokens versus 66K.
  • Inkling has downloadable open weights; the other is API-only.

Side by side

Claude Opus 4.5 and Inkling specifications
Claude Opus 4.5Inkling
ProviderAnthropicThinking Machines Lab
Noometry Index50.544.1
Released2025-11-012026-07-15
WeightsProprietaryOpen
Context window200K66K
Max output64K66K
Input $ / M tokens$5$1.87
Output $ / M tokens$25$4.68
Results tracked6941

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

Category by category

Coding Claude Opus 4.5 leads

Claude Opus 4.5: 54.8 (#27), Inkling: 34.5 (#234)

Coding benchmarks
BenchmarkClaude Opus 4.5Inkling
LMArena WebDev14941413
WeirdML63.7%32.3%
LMArena Coding15041464
ALE-Bench1,025946
SWE-bench Verified76.7%—
FrontierCode—14%
SWE-bench Verified (bash only)76.8%—
SWE-bench Multilingual70.7%—
FrontierSWE—4.1%
SciCode—47%
GSO26.5%—
AlgoTune1.77—

Agentic & Tool Use Claude Opus 4.5 leads

Claude Opus 4.5: 47.3 (#12), Inkling: 29.6 (#85)

Agentic & Tool Use benchmarks
BenchmarkClaude Opus 4.5Inkling
τ²-bench Banking24.7%25%
Terminal-Bench63.1%—
APEX-Agents—33.8%
Berkeley Function Calling Leaderboard77.5%—
GDPval45.5%—
Remote Labor Index3.8%—
τ²-bench Airline84%—
τ²-bench Retail79.6%—
τ²-bench Telecom92.3%—
Cybench82%—
DeepResearch Bench54.8%—
OSWorld66.3%—
BALROG43.5%—
LMArena Search1180—
METR Time Horizons75%—
Vending-Bench 24,967—

Reasoning Claude Opus 4.5 leads

Claude Opus 4.5: 42.6 (#51), Inkling: 40.4 (#56)

Reasoning benchmarks
BenchmarkClaude Opus 4.5Inkling
ARC-AGI-237.6%36.5%
SimpleBench62%50%
ARC-AGI-180%79.5%
Chess Puzzles12%21%
LMArena Hard Prompts14761451
DTBench89.9%87.5%
LMCA44.5%37.6%
Epoch Capabilities Index150.09148.54
Kagi LLM Benchmark80.2%—
NYT Connections (extended)52.5%—
CritPt—5.4%
EnigmaEval11.9%—
EBR-Bench14.3%—
Mystery Game Puzzles22%—
ForecastBench60.7—

Math Claude Opus 4.5 leads

Claude Opus 4.5: 38.6 (#132), Inkling: 31.3 (#225)

Math benchmarks
BenchmarkClaude Opus 4.5Inkling
FrontierMath (Tiers 1-3)34.4%33.3%
FrontierMath Tier 44.9%4.9%
OTIS Mock AIME 2024-202586.1%88.9%
ProofBench36%0%
LMArena Math14631479
FrontierMath (Feb 2025 set)20.7%—
FrontierMath Tier 4 (v1)4.2%—

Knowledge Claude Opus 4.5 leads

Claude Opus 4.5: 56.5 (#44), Inkling: 55.1 (#49)

Knowledge benchmarks
BenchmarkClaude Opus 4.5Inkling
GPQA Diamond86%88.3%
SimpleQA Verified45.7%40.3%
LMArena Expert14871465
Humanity's Last Exam25.2%—
Vectara Hallucination Rate10.9%—

Multimodal Not comparable

Claude Opus 4.5: 31.4 (#107), Inkling: —

Multimodal benchmarks
BenchmarkClaude Opus 4.5Inkling
GeoBench75%—
VPCT40%—
Furniture Assembly28.3%—
LMArena Document1462—

Multilingual Too close to call

Claude Opus 4.5: 54.3 (#47), Inkling: 54.0 (#52)

Multilingual benchmarks
BenchmarkClaude Opus 4.5Inkling
LMArena Non-English14381434
LMArena Chinese14701490
LMArena French14711458
LMArena German14491446
LMArena Japanese14161429
LMArena Korean14241404
LMArena Russian14471429
LMArena Spanish14581448

Instruction Following Claude Opus 4.5 leads

Claude Opus 4.5: 77.5 (#19), Inkling: 75.1 (#71)

Instruction Following benchmarks
BenchmarkClaude Opus 4.5Inkling
LMArena Instruction Following14781426

Long Context Claude Opus 4.5 leads

Claude Opus 4.5: 46.5 (#22), Inkling: 43.8 (#86)

Long Context benchmarks
BenchmarkClaude Opus 4.5Inkling
LMArena Longer Query14801434
CL-bench21.1%—

Writing & Preference Claude Opus 4.5 leads

Claude Opus 4.5: 68.1 (#28), Inkling: 65.2 (#51)

Writing & Preference benchmarks
BenchmarkClaude Opus 4.5Inkling
LMArena Text14511441
LMArena Creative Writing14451387
EQ-Bench Creative Writing16871611
LMArena Multi-Turn14661436
EQ-Bench 4—1226

Frequently asked questions

Is Claude Opus 4.5 better than Inkling?

Claude Opus 4.5 is the stronger model overall, scoring 50.5 to 44.1 on the Noometry Index. Inkling costs 3.9× less per token, which makes it the better buy when Claude Opus 4.5's lead doesn't matter for your workload.

Which is cheaper, Claude Opus 4.5 or Inkling?

Inkling is cheaper. It lists at $1.87 per million input tokens and $4.68 per million output tokens; Claude Opus 4.5 lists at $5 and $25.

Is Claude Opus 4.5 or Inkling better for coding?

Claude Opus 4.5 scores higher on coding benchmarks: 54.8 versus 34.5 in the Noometry coding category.

Which has the bigger context window?

Claude Opus 4.5 does, with 200K tokens against 66K.

How many benchmarks do Claude Opus 4.5 and Inkling share?

35 benchmarks have published results for both models. Claude Opus 4.5 has 69 scored results on Noometry and Inkling has 41.

Related comparisons

Go deeper