Noometry

Model comparison

Claude Opus 5.5 vs Qwen3.5-Flash

Claude Opus 5.5 is the stronger model overall, scoring 68.5 to 42.3 on the Noometry Index. Qwen3.5-Flash costs 46× less per token, which makes it the better buy when Claude Opus 5.5's lead doesn't matter for your workload.

Last verified . 19 shared benchmarks.

Claude Opus 5.5 Anthropic

68.5

Rank #3 Confirmed

Qwen3.5-Flash Alibaba (Qwen)

42.3

Rank #105 Confirmed

Summary

  • They share 19 benchmarks with published results for both. Claude Opus 5.5 scores higher in 8 categories and Qwen3.5-Flash in 0 categories; 8 gaps are clear of the uncertainty.
  • The widest gap is in math, where Claude Opus 5.5 leads 92.4 to 36.3.
  • The biggest single-benchmark swing is FrontierMath (Tiers 1-3): 91.2% for Claude Opus 5.5 and 18.2% for Qwen3.5-Flash.
  • Qwen3.5-Flash is cheaper at $0.10 / $0.40 per million input/output tokens, against $4 / $20 for Claude Opus 5.5.

Side by side

Claude Opus 5.5Qwen3.5-Flash
ProviderAnthropicAlibaba (Qwen)
Noometry Index68.542.3
Released2026-09-222026-02-23
WeightsProprietaryProprietary
Context window1M1M
Max output128K66K
Input $ / M tokens$4$0.10
Output $ / M tokens$20$0.40
Results tracked3532

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Category by category

Coding Claude Opus 5.5 leads

Claude Opus 5.5: 71.4 (#1), Qwen3.5-Flash: 33.9 (#234)

BenchmarkClaude Opus 5.5Qwen3.5-Flash
LMArena WebDev18201243
LMArena Coding15451412
FrontierCode54.4%—
CursorBench57.8%—
FrontierSWE62.3%—
SciCode66.9%—
MirrorCode77.4%—
ALE-Bench—221.8

Agentic & Tool Use Not comparable

Claude Opus 5.5: 45.3 (#13), Qwen3.5-Flash: —

BenchmarkClaude Opus 5.5Qwen3.5-Flash
APEX-Agents73.5%—
GDP.pdf30.6%—
Vending-Bench 2—462.69

Reasoning Claude Opus 5.5 leads

Claude Opus 5.5: 79.5 (#2), Qwen3.5-Flash: 32.9 (#63)

BenchmarkClaude Opus 5.5Qwen3.5-Flash
LMArena Hard Prompts15451404
Mystery Game Puzzles71%20%
DTBench98.9%82.9%
LMCA68.2%29.1%
ARC-AGI-292.5%—
NYT Connections (extended)88.5%—
ARC-AGI-197.5%—
CritPt31.7%—
Chess Puzzles—21%
EBR-Bench71.4%—
Epoch Capabilities Index—143.98

Math Claude Opus 5.5 leads

Claude Opus 5.5: 92.4 (#2), Qwen3.5-Flash: 36.3 (#117)

BenchmarkClaude Opus 5.5Qwen3.5-Flash
FrontierMath (Tiers 1-3)91.2%18.2%
OTIS Mock AIME 2024-2025100%84.4%
FrontierMath Tier 495%—
ProofBench100%—
LMArena Math—1407
FrontierMath (Feb 2025 set)—6.2%
FrontierMath Tier 4 (v1)—0%

Knowledge Claude Opus 5.5 leads

Claude Opus 5.5: 66.6 (#9), Qwen3.5-Flash: 43.2 (#84)

BenchmarkClaude Opus 5.5Qwen3.5-Flash
GPQA Diamond90.6%82.3%
SimpleQA Verified72.2%20.3%
LMArena Expert15641408
Vectara Hallucination Rate—10.5%

Multimodal Not comparable

Claude Opus 5.5: 56.5 (#2), Qwen3.5-Flash: —

BenchmarkClaude Opus 5.5Qwen3.5-Flash
Furniture Assembly83.3%—

Multilingual Claude Opus 5.5 leads

Claude Opus 5.5: 59.8 (#1), Qwen3.5-Flash: 50.7 (#116)

BenchmarkClaude Opus 5.5Qwen3.5-Flash
LMArena Non-English15131385
LMArena Chinese15721446
LMArena Russian15321379
LMArena French—1412
LMArena German—1389
LMArena Japanese—1369
LMArena Korean—1344
LMArena Spanish—1399

Instruction Following Claude Opus 5.5 leads

Claude Opus 5.5: 80.1 (#2), Qwen3.5-Flash: 72.8 (#133)

BenchmarkClaude Opus 5.5Qwen3.5-Flash
LMArena Instruction Following15351374

Long Context Claude Opus 5.5 leads

Claude Opus 5.5: 47.3 (#18), Qwen3.5-Flash: 42.4 (#119)

BenchmarkClaude Opus 5.5Qwen3.5-Flash
LMArena Longer Query15401392

Writing & Preference Claude Opus 5.5 leads

Claude Opus 5.5: 78.7 (#3), Qwen3.5-Flash: 58.2 (#117)

BenchmarkClaude Opus 5.5Qwen3.5-Flash
LMArena Text15181397
LMArena Creative Writing15381343
LMArena Multi-Turn15201393
EQ-Bench Creative Writing2050—

Frequently asked questions

Is Claude Opus 5.5 better than Qwen3.5-Flash?

Claude Opus 5.5 is the stronger model overall, scoring 68.5 to 42.3 on the Noometry Index. Qwen3.5-Flash costs 46× less per token, which makes it the better buy when Claude Opus 5.5's lead doesn't matter for your workload.

Which is cheaper, Claude Opus 5.5 or Qwen3.5-Flash?

Qwen3.5-Flash is cheaper. It lists at $0.10 per million input tokens and $0.40 per million output tokens; Claude Opus 5.5 lists at $4 and $20.

Is Claude Opus 5.5 or Qwen3.5-Flash better for coding?

Claude Opus 5.5 scores higher on coding benchmarks: 71.4 versus 33.9 in the Noometry coding category.

Which has the bigger context window?

Both accept 1M tokens.

How many benchmarks do Claude Opus 5.5 and Qwen3.5-Flash share?

19 benchmarks have published results for both models. Claude Opus 5.5 has 35 scored results on Noometry and Qwen3.5-Flash has 32.

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