Model comparison
Claude 3.5 Sonnet vs Composer 2 Fast
Head-to-head evidence from 0 shared benchmark results across 0 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: Claude 3.5 Sonnet #139 (Estimated); Composer 2 Fast unranked (Not scored). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. Claude 3.5 Sonnet and Composer 2 Fast share 0 comparable benchmark results. 0 of 8 categories are comparable. 4 results are unique to Claude 3.5 Sonnet; 1 to Composer 2 Fast.
Updated July 28, 2026- Shared results
- 0
- Claude 3.5 Sonnet only
- 4
- Composer 2 Fast only
- 1
- Comparable categories
- 0 / 8
Benchmark data for Claude 3.5 Sonnet and Composer 2 Fast is coming soon on BenchLM.
Confidence note. This is a partial-evidence comparison with 0 shared benchmark results across 0 evidence categories; 0 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.
Why this result
BenchLM has partial data for these models, but not enough overlapping benchmark coverage to produce a fair score-level comparison yet.
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | Claude 3.5 Sonnet | Composer 2 Fast | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | Claude 3.5 Sonnet$3 input / $15 output | Composer 2 FastNot available | A complete price comparison is not available. |
| Generation speedtokens per second | Claude 3.5 SonnetNot available | Composer 2 FastNot available | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | Claude 3.5 SonnetNot available | Composer 2 FastNot available | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | Claude 3.5 Sonnet200K | Composer 2 Fast200K | Listed context windows are equal. |
Benchmark Deep Dive
Coding2 benchmarks
Knowledge1 benchmarks
| Benchmark | Claude 3.5 Sonnet | Composer 2 Fast | Result |
|---|---|---|---|
| GPQASource | 59.4% | — | Not comparable |
Frequently Asked Questions (3)
Can I compare Claude 3.5 Sonnet and Composer 2 Fast on BenchLM yet?
Not fully yet. BenchLM is tracking both models, but the sourced benchmark breakdown for this comparison is still coming soon.
Why does this comparison show “coming soon”?
BenchLM only shows category winners and benchmark-level calls when we have sourced results that can be compared fairly. For these models, the public benchmark coverage is not complete enough yet.
What data is available for Claude 3.5 Sonnet and Composer 2 Fast today?
Claude 3.5 Sonnet: $3.00 input / $15.00 output per 1M tokens Both model pages still include creator, context window, reasoning mode, and other metadata while benchmark coverage fills in.
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