Noometry

Model comparison

Claude Opus 4.5 vs Mistral Small

Claude Opus 4.5 is the stronger model overall, scoring 50.5 to 33.4 on the Noometry Index. Mistral Small costs 38× less per token, which makes it the better buy when Claude Opus 4.5's lead doesn't matter for your workload.

Last verified . 25 shared benchmarks.

Claude Opus 4.5 Anthropic

50.5

Rank #47 Confirmed

Mistral Small Mistral AI

33.4

Rank #243 Confirmed

Summary

  • They share 25 benchmarks with published results for both. Claude Opus 4.5 scores higher in 9 categories and Mistral Small in 1 category; 10 gaps are clear of the uncertainty.
  • The widest gap is in knowledge, where Claude Opus 4.5 leads 56.5 to 31.0.
  • The biggest single-benchmark swing is OTIS Mock AIME 2024-2025: 86.1% for Claude Opus 4.5 and 5.8% for Mistral Small.
  • Mistral Small is cheaper at $0.15 / $0.60 per million input/output tokens, against $5 / $25 for Claude Opus 4.5.
  • Mistral Small accepts more context: 262K tokens versus 200K.
  • Mistral Small has downloadable open weights; the other is API-only.

Side by side

Claude Opus 4.5Mistral Small
ProviderAnthropicMistral AI
Noometry Index50.533.4
Released2025-11-012024-02-26
WeightsProprietaryOpen
Context window200K262K
Max output64K256K
Input $ / M tokens$5$0.15
Output $ / M tokens$25$0.60
Results tracked6939

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Category by category

Coding Claude Opus 4.5 leads

Claude Opus 4.5: 54.8 (#27), Mistral Small: 34.0 (#247)

BenchmarkClaude Opus 4.5Mistral Small
LMArena Coding15041362
ALE-Bench1,025497.62
SWE-bench Verified76.7%—
SWE-bench Verified (bash only)76.8%—
LMArena WebDev1494—
SWE-bench Multilingual70.7%—
SciCode—26.5%
GSO26.5%—
WeirdML63.7%—
BigCodeBench Instruct—36.1%
LiveBench Coding—36.2%
BigCodeBench Complete—46.6%
AlgoTune1.77—

Agentic & Tool Use Claude Opus 4.5 leads

Claude Opus 4.5: 47.3 (#12), Mistral Small: 28.1 (#93)

BenchmarkClaude Opus 4.5Mistral Small
Berkeley Function Calling Leaderboard77.5%37.1%
Terminal-Bench63.1%—
GDPval45.5%—
Remote Labor Index3.8%—
τ²-bench Airline84%—
τ²-bench Banking24.7%—
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), Mistral Small: 19.8 (#250)

BenchmarkClaude Opus 4.5Mistral Small
Kagi LLM Benchmark80.2%37.8%
LMArena Hard Prompts14761335
DTBench89.9%70.9%
LMCA44.5%20.6%
ARC-AGI-237.6%—
SimpleBench62%—
NYT Connections (extended)52.5%—
ARC-AGI-180%—
CritPt—0%
Chess Puzzles12%—
EnigmaEval11.9%—
EBR-Bench14.3%—
LiveBench Reasoning—44.8%
Mystery Game Puzzles22%—
LiveBench Data Analysis—53.7%
Epoch Capabilities Index150.09—
ForecastBench60.7—
LiveBench—44%

Math Claude Opus 4.5 leads

Claude Opus 4.5: 38.6 (#132), Mistral Small: 16.4 (#293)

BenchmarkClaude Opus 4.5Mistral Small
OTIS Mock AIME 2024-202586.1%5.8%
LMArena Math14631341
FrontierMath (Tiers 1-3)34.4%—
FrontierMath Tier 44.9%—
ProofBench36%—
LiveBench Math—39.9%
MATH Level 5—46.8%
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), Mistral Small: 31.0 (#222)

BenchmarkClaude Opus 4.5Mistral Small
GPQA Diamond86%47.5%
Vectara Hallucination Rate10.9%5.1%
LMArena Expert14871291
Humanity's Last Exam25.2%—
SimpleQA Verified45.7%—
MMLU—68.7%

Multimodal Mistral Small leads

Claude Opus 4.5: 31.4 (#107), Mistral Small: 33.5 (#96)

BenchmarkClaude Opus 4.5Mistral Small
LMArena Vision—1142
GeoBench75%—
VPCT40%—
Furniture Assembly28.3%—
LMArena Document1462—

Multilingual Claude Opus 4.5 leads

Claude Opus 4.5: 54.3 (#47), Mistral Small: 45.5 (#169)

BenchmarkClaude Opus 4.5Mistral Small
LMArena Non-English14381315
LMArena Chinese14701340
LMArena French14711337
LMArena German14491340
LMArena Japanese14161275
LMArena Korean14241259
LMArena Russian14471324
LMArena Spanish14581346

Instruction Following Claude Opus 4.5 leads

Claude Opus 4.5: 77.5 (#19), Mistral Small: 66.4 (#209)

BenchmarkClaude Opus 4.5Mistral Small
LMArena Instruction Following14781310
LiveBench Instruction Following—63.7%

Long Context Claude Opus 4.5 leads

Claude Opus 4.5: 46.5 (#22), Mistral Small: 40.4 (#156)

BenchmarkClaude Opus 4.5Mistral Small
LMArena Longer Query14801327
CL-bench21.1%—

Writing & Preference Claude Opus 4.5 leads

Claude Opus 4.5: 68.1 (#28), Mistral Small: 52.5 (#171)

BenchmarkClaude Opus 4.5Mistral Small
LMArena Text14511338
LMArena Creative Writing14451305
LMArena Multi-Turn14661344
EQ-Bench Creative Writing1687—
LiveBench Language—30.5%

Frequently asked questions

Is Claude Opus 4.5 better than Mistral Small?

Claude Opus 4.5 is the stronger model overall, scoring 50.5 to 33.4 on the Noometry Index. Mistral Small costs 38× 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 Mistral Small?

Mistral Small is cheaper. It lists at $0.15 per million input tokens and $0.60 per million output tokens; Claude Opus 4.5 lists at $5 and $25.

Is Claude Opus 4.5 or Mistral Small better for coding?

Claude Opus 4.5 scores higher on coding benchmarks: 54.8 versus 34.0 in the Noometry coding category.

Which has the bigger context window?

Mistral Small does, with 262K tokens against 200K.

How many benchmarks do Claude Opus 4.5 and Mistral Small share?

25 benchmarks have published results for both models. Claude Opus 4.5 has 69 scored results on Noometry and Mistral Small has 39.

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