Claude Opus 4.5 vs Composer 2

Side-by-side benchmark comparison across agentic, coding, multimodal, knowledge, reasoning, and math workflows.

Claude Opus 4.5 is clearly ahead on the aggregate, 66 to 62. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.

Composer 2 is the reasoning model in the pair, while Claude Opus 4.5 is not. That usually helps on harder chain-of-thought-heavy tests, but it can also mean more latency and more token spend in real use.

Quick Verdict

Pick Claude Opus 4.5 if you want the stronger benchmark profile. Composer 2 only becomes the better choice if agentic is the priority or you want the stronger reasoning-first profile.

Agentic

Composer 2

Claude Opus 4.5

59.3

Composer 2

61.7

59.3%
Terminal-Bench 2.0
61.7%

Coding

Coming soon

Comparable scores for this category are coming soon. One or both models do not have sourced results here yet.

80.9%
SWE-bench Verified
Coming soon
Coming soon
SWE Multilingual
73.7%
Coming soon
React Native Evals
97.2%

Multimodal & Grounded

Coming soon

Benchmark data for this category is coming soon.

Reasoning

Coming soon

Comparable scores for this category are coming soon. One or both models do not have sourced results here yet.

37.6%
ARC-AGI-2
Coming soon

Knowledge

Coming soon

Comparable scores for this category are coming soon. One or both models do not have sourced results here yet.

95%
SimpleQA
Coming soon

Instruction Following

Coming soon

Comparable scores for this category are coming soon. One or both models do not have sourced results here yet.

90%
IFEval
Coming soon

Multilingual

Coming soon

Benchmark data for this category is coming soon.

Mathematics

Coming soon

Comparable scores for this category are coming soon. One or both models do not have sourced results here yet.

99%
AIME 2024
Coming soon
98%
AIME 2025
Coming soon
96%
BRUMO 2025
Coming soon

Frequently Asked Questions

Which is better, Claude Opus 4.5 or Composer 2?

Claude Opus 4.5 is ahead overall, 66 to 62. The biggest single separator in this matchup is Terminal-Bench 2.0, where the scores are 59.3% and 61.7%.

Which is better for agentic tasks, Claude Opus 4.5 or Composer 2?

Composer 2 has the edge for agentic tasks in this comparison, averaging 61.7 versus 59.3. Inside this category, Terminal-Bench 2.0 is the benchmark that creates the most daylight between them.

Last updated: March 18, 2026

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