Model comparison
Claude Sonnet 4.6 vs Composer 2 Fast
Head-to-head evidence from 1 shared benchmark result across 1 category. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: Claude Sonnet 4.6 #35 (Supported); Composer 2 Fast unranked (Not scored). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. Claude Sonnet 4.6 and Composer 2 Fast share 1 comparable benchmark result. 0 of 8 categories are comparable. 32 results are unique to Claude Sonnet 4.6; 0 to Composer 2 Fast.
Updated July 27, 2026- Shared results
- 1
- Claude Sonnet 4.6 only
- 32
- Composer 2 Fast only
- 0
- Comparable categories
- 0 / 8
Benchmark data for Claude Sonnet 4.6 and Composer 2 Fast is coming soon on BenchLM.
Confidence note. This is a partial-evidence comparison with 1 shared benchmark result across 1 evidence category; 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.
Category breakdown
Exact category averages are shown below. Not measured means BenchLM does not have enough sourced public coverage for that model and category.
| Category | Claude Sonnet 4.6 | Δ | Composer 2 Fast |
|---|---|---|---|
| Agentic | Claude Sonnet 4.665.2 | MarginNo overlap | Composer 2 FastNot measured |
| Coding | Claude Sonnet 4.669.1 | MarginNo overlap | Composer 2 FastNot measured |
| Knowledge | Claude Sonnet 4.666.0 | MarginNo overlap | Composer 2 FastNot measured |
| Math | Claude Sonnet 4.626.4 | MarginNo overlap | Composer 2 FastNot measured |
| Multimodal | Claude Sonnet 4.677.4 | MarginNo overlap | Composer 2 FastNot measured |
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | Claude Sonnet 4.6 | Composer 2 Fast | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | Claude Sonnet 4.6$3 input / $15 output | Composer 2 FastNot available | A complete price comparison is not available. |
| Generation speedtokens per second | Claude Sonnet 4.644 tok/s | Composer 2 FastNot available | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | Claude Sonnet 4.61.48 s | Composer 2 FastNot available | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | Claude Sonnet 4.6200K | Composer 2 Fast200K | Listed context windows are equal. |
Benchmark Deep Dive
Agentic8 benchmarks
| Benchmark | Claude Sonnet 4.6 | Composer 2 Fast | Result |
|---|---|---|---|
| Terminal-Bench 2.0Source | 59.1% | — | Not comparable |
| OSWorld-VerifiedSource | 72.1% | — | Not comparable |
| Claw-EvalSource | 67.8% | — | Not comparable |
| CyberGymSource | 65.2% | — | Not comparable |
| τ²-bench resultsSource | 79.5% | — | Not comparable |
| Gert LabsSource | 62.92% | — | Not comparable |
| OSWorld 2.0Source | 8.3% | — | Not comparable |
| JobBenchSource | 36.9% | — | Not comparable |
Coding7 benchmarks
| Benchmark | Claude Sonnet 4.6 | Composer 2 Fast | Result |
|---|---|---|---|
| SWE-bench VerifiedSource | 79.6% | — | Not comparable |
| SWE-RebenchSource | 60.7% | — | Not comparable |
| React Native EvalsSource | 80.6% | 94.9% | Composer 2 Fast leads |
| Vibe Code BenchSource | 51.48% | — | Not comparable |
| cursorBench31Source | 48.8% | — | Not comparable |
| AA-SciCodeSource | 46.9% | — | Not comparable |
| FrontierCode 1.1 MainSource | 24.3% | — | Not comparable |
Reasoning2 benchmarks
Knowledge10 benchmarks
| Benchmark | Claude Sonnet 4.6 | Composer 2 Fast | Result |
|---|---|---|---|
| GPQASource | 89.9% | — | Not comparable |
| SuperGPQASource | 95% | — | Not comparable |
| MMLU-ProSource | 79.2% | — | Not comparable |
| HLESource | 49% | — | Not comparable |
| Artificial Analysis Intelligence IndexSource | 35.9% | — | Not comparable |
| AA-GPQA DiamondSource | 79.9% | — | Not comparable |
| AA-HLESource | 13.2% | — | Not comparable |
| AA-Omniscience IndexSource | -2.9% | — | Not comparable |
| AA-Omniscience AccuracySource | 38.0% | — | Not comparable |
| AA-Omniscience Hallucination RateSource | 65.9% | — | Not comparable |
Math2 benchmarks
Multimodal3 benchmarks
Inst. Following1 benchmarks
| Benchmark | Claude Sonnet 4.6 | Composer 2 Fast | Result |
|---|---|---|---|
| AA-IFBenchSource | 41.2% | — | Not comparable |
Frequently Asked Questions (3)
Can I compare Claude Sonnet 4.6 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 Sonnet 4.6 and Composer 2 Fast today?
Claude Sonnet 4.6: $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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