Model comparison
Composer 2 vs GPT-5.6 Sol
Head-to-head evidence from 2 shared benchmark results across 2 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: Composer 2 unranked (Not scored); GPT-5.6 Sol #3 (Supported). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. Composer 2 and GPT-5.6 Sol share 2 comparable benchmark results. 2 of 8 categories are comparable. 3 results are unique to Composer 2; 44 to GPT-5.6 Sol.
Updated July 23, 2026- Shared results
- 2
- Composer 2 only
- 3
- GPT-5.6 Sol only
- 44
- Comparable categories
- 2 / 8
Treat this as a split decision. Composer 2 makes more sense if you want the cheaper token bill; GPT-5.6 Sol is the better fit if agentic is the priority or you need the larger 1M context window.
Confidence note. This is a partial-evidence comparison with 2 shared benchmark results across 2 evidence categories; 2 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.
Why this result
Composer 2 and GPT-5.6 Sol finish on the same BenchAlign overall score, so this is less about a single winner and more about where the edge shows up. The BenchAlign headline says tie; the benchmark table is where the real choice happens.
GPT-5.6 Sol is also the more expensive model on tokens at $5.00 input / $30.00 output per 1M tokens, versus $0.50 input / $2.50 output per 1M tokens for Composer 2. That is roughly 12.0x on output cost alone. GPT-5.6 Sol gives you the larger context window at 1M, compared with 200K for Composer 2.
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 | Composer 2 | Δ | GPT-5.6 Sol |
|---|---|---|---|
| Agentic | Composer 261.7 | Margin→ 30.3 | GPT-5.6 Sol92.0 |
| Coding | Composer 258.0 | Margin→ 6.6 | GPT-5.6 Sol64.6 |
| Knowledge | Composer 2Not measured | MarginNo overlap | GPT-5.6 Sol94.6 |
| Math | Composer 2Not measured | MarginNo overlap | GPT-5.6 Sol87.5 |
| Multimodal | Composer 2Not measured | MarginNo overlap | GPT-5.6 Sol83.0 |
Decisive benchmark drivers
The largest measured benchmark gaps in this matchup, with exact reported values.
More
- Source ↗
Terminal-Bench 2.0
AgenticA 61.7%B 91.9%Winner: GPT-5.6 SolΔ 30.2Terminal-Bench 2.0: Composer 2 scored 61.7%; GPT-5.6 Sol scored 91.9%. GPT-5.6 Sol wins this benchmark.
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | Composer 2 | GPT-5.6 Sol | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | Composer 2$0.5 input / $2.5 output | GPT-5.6 Sol$5 input / $30 output | Composer 2 has the lower combined listed price. |
| Generation speedtokens per second | Composer 2Not available | GPT-5.6 SolNot available | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | Composer 2Not available | GPT-5.6 SolNot available | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | Composer 2200K | GPT-5.6 Sol1M | GPT-5.6 Sol lists the larger context window. |
Benchmark Deep Dive
AgenticGPT-5.6 Sol wins17 benchmarks
| Benchmark | Composer 2 | GPT-5.6 Sol | Result |
|---|---|---|---|
| Terminal-Bench 2.0Source | 61.7% | 91.9% | GPT-5.6 Sol leads |
| BrowseCompSource | — | 92.2% | Not comparable |
| OSWorld 2.0Source | — | 62.6% | Not comparable |
| CyberGymSource | — | 84.5% | Not comparable |
| ExploitGymSource | — | 33.7% | Not comparable |
| ToolathlonSource | — | 58% | Not comparable |
| AA Agentic IndexSource | — | 54.0% | Not comparable |
| τ²-bench resultsSource | — | 85.1% | Not comparable |
| GDPval-AASource | — | 61.8% | Not comparable |
| GDPval-AASource | — | 1736 | Not comparable |
| AA BriefcaseSource | — | 1501 | Not comparable |
| AA ITBenchSource | — | 56.2% | Not comparable |
| AA Tau3 BankingSource | — | 33.0% | Not comparable |
| AA AutomationBenchSource | — | 51.2% | Not comparable |
| AA Harvey LABSource | — | 87.2% | Not comparable |
| terminalBenchHardSource | — | 65.9% | Not comparable |
| aaTerminalBench21Source | — | 88% | Not comparable |
CodingGPT-5.6 Sol wins11 benchmarks
| Benchmark | Composer 2 | GPT-5.6 Sol | Result |
|---|---|---|---|
| SWE MultilingualSource | 73.7% | — | Not comparable |
| SWE-RebenchSource | 58% | — | Not comparable |
| React Native EvalsSource | 96.1% | — | Not comparable |
| Terminal-Bench 2.0Source | 61.7% | 91.9% | GPT-5.6 Sol leads |
| SWE-bench ProSource | — | 64.6% | Not comparable |
| deepSweSource | — | 72.7% | Not comparable |
| FrontierCode 1.1 ExtendedSource | — | 60.6% | Not comparable |
| cursorBench32Source | — | 67.2% | Not comparable |
| VulcanBench v3Source | — | 87.0% | Not comparable |
| AA Coding IndexSource | — | 77.4% | Not comparable |
| AA-SciCodeSource | — | 56.1% | Not comparable |
Reasoning4 benchmarks
Knowledge10 benchmarks
| Benchmark | Composer 2 | GPT-5.6 Sol | Result |
|---|---|---|---|
| GPQASource | — | 94.6% | Not comparable |
| GPQA-DSource | — | 94.6% | Not comparable |
| HealthBench ProfessionalSource | — | 60.5% | Not comparable |
| HealthBench HardSource | — | 33.1% | Not comparable |
| Artificial Analysis Intelligence IndexSource | — | 58.9% | Not comparable |
| AA-GPQA DiamondSource | — | 94.1% | Not comparable |
| AA-HLESource | — | 47.2% | Not comparable |
| AA-Omniscience IndexSource | — | 21.7% | Not comparable |
| AA-Omniscience AccuracySource | — | 58.5% | Not comparable |
| AA-Omniscience Hallucination RateSource | — | 88.8% | Not comparable |
Math3 benchmarks
Multimodal3 benchmarks
Inst. Following1 benchmarks
| Benchmark | Composer 2 | GPT-5.6 Sol | Result |
|---|---|---|---|
| AA-IFBenchSource | — | 72.7% | Not comparable |
Frequently Asked Questions (3)
Which is better, Composer 2 or GPT-5.6 Sol?
Composer 2 and GPT-5.6 Sol are tied on the BenchAlign overall score, so the right pick depends on which category matters most for your use case.
Which is better for coding, Composer 2 or GPT-5.6 Sol?
GPT-5.6 Sol has the edge for coding in this comparison, averaging 64.6 versus 58. Inside this category, Terminal-Bench 2.0 is the benchmark that creates the most daylight between them.
Which is better for agentic tasks, Composer 2 or GPT-5.6 Sol?
GPT-5.6 Sol has the edge for agentic tasks in this comparison, averaging 92 versus 61.7. Inside this category, Terminal-Bench 2.0 is the benchmark that creates the most daylight between them.
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