Model comparison
Claude Opus 4.8 vs Composer 2.5
Head-to-head evidence from 5 shared benchmark results across 2 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: Claude Opus 4.8 #5 (Supported); Composer 2.5 unranked (Not scored). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. Claude Opus 4.8 and Composer 2.5 share 5 comparable benchmark results. 1 of 8 categories are comparable. 48 results are unique to Claude Opus 4.8; 0 to Composer 2.5.
Updated July 23, 2026- Shared results
- 5
- Claude Opus 4.8 only
- 48
- Composer 2.5 only
- 0
- Comparable categories
- 1 / 8
Treat this as a split decision. Claude Opus 4.8 makes more sense if agentic is the priority or you need the larger 1M context window; Composer 2.5 is the better fit if you want the cheaper token bill.
Confidence note. This is a partial-evidence comparison with 5 shared benchmark results across 2 evidence categories; 1 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.
Why this result
Claude Opus 4.8 and Composer 2.5 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.
Claude Opus 4.8 is also the more expensive model on tokens at $5.00 input / $25.00 output per 1M tokens, versus $0.50 input / $2.50 output per 1M tokens for Composer 2.5. That is roughly 10.0x on output cost alone. Claude Opus 4.8 gives you the larger context window at 1M, compared with 200K for Composer 2.5.
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 Opus 4.8 | Δ | Composer 2.5 |
|---|---|---|---|
| Agentic | Claude Opus 4.880.3 | Margin← 11.0 | Composer 2.569.3 |
| Coding | Claude Opus 4.881.1 | MarginNo overlap | Composer 2.5Not measured |
| Knowledge | Claude Opus 4.862.7 | MarginNo overlap | Composer 2.5Not measured |
| Math | Claude Opus 4.853.9 | MarginNo overlap | Composer 2.5Not measured |
| Multimodal | Claude Opus 4.877.0 | MarginNo overlap | Composer 2.5Not measured |
Decisive benchmark drivers
The largest measured benchmark gaps in this matchup, with exact reported values.
More
- Source ↗
Terminal-Bench 2.0
AgenticA 74.6%B 69.3%Winner: Claude Opus 4.8Δ 5.3Terminal-Bench 2.0: Claude Opus 4.8 scored 74.6%; Composer 2.5 scored 69.3%. Claude Opus 4.8 wins this benchmark.
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | Claude Opus 4.8 | Composer 2.5 | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | Claude Opus 4.8$5 input / $25 output | Composer 2.5$0.5 input / $2.5 output | Composer 2.5 has the lower combined listed price. |
| Generation speedtokens per second | Claude Opus 4.8Not available | Composer 2.5Not available | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | Claude Opus 4.8Not available | Composer 2.5Not available | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | Claude Opus 4.81M | Composer 2.5200K | Claude Opus 4.8 lists the larger context window. |
Benchmark Deep Dive
AgenticClaude Opus 4.8 wins21 benchmarks
| Benchmark | Claude Opus 4.8 | Composer 2.5 | Result |
|---|---|---|---|
| Terminal-Bench 2.0Source | 74.6% | 69.3% | Claude Opus 4.8 leads |
| BrowseCompSource | 84.3% | — | Not comparable |
| DeepSearchQASource | 93.1% | — | Not comparable |
| OSWorld-VerifiedSource | 83.4% | — | Not comparable |
| Finance Agent v2Source | 53.9% | — | Not comparable |
| GDPval-AASource | 1594 | — | Not comparable |
| MCP AtlasSource | 82.2% | — | Not comparable |
| ToolathlonSource | 59.9% | — | Not comparable |
| Gert LabsSource | 72.97% | — | Not comparable |
| AA Agentic IndexSource | 47.2% | — | Not comparable |
| τ²-bench resultsSource | 94.4% | — | Not comparable |
| GDPval-AASource | 54.7% | — | Not comparable |
| ResearchClawBenchSource | 21.1% | — | Not comparable |
| OSWorld 2.0Source | 20.6% | — | Not comparable |
| AA BriefcaseSource | 1347 | — | Not comparable |
| AA AutomationBenchSource | 48.5% | — | Not comparable |
| AA EnterpriseOps-GymSource | 44.0% | — | Not comparable |
| AA Harvey LABSource | 91.1% | — | Not comparable |
| AA Tau3 BankingSource | 27.6% | — | Not comparable |
| terminalBenchHardSource | 58.3% | — | Not comparable |
| aaTerminalBench21Source | 84.6% | — | Not comparable |
Coding10 benchmarks
| Benchmark | Claude Opus 4.8 | Composer 2.5 | Result |
|---|---|---|---|
| SWE-bench VerifiedSource | 88.6% | — | Not comparable |
| SWE-bench ProSource | 69.2% | — | Not comparable |
| SWE MultilingualSource | 84.4% | 79.8% | Claude Opus 4.8 leads |
| SWE MultimodalSource | 38.4% | — | Not comparable |
| Terminal-Bench 2.0Source | 74.6% | 69.3% | Claude Opus 4.8 leads |
| cursorBench31Source | 58.4% | 63.2% | Composer 2.5 leads |
| cursorBench32Source | 62.3% | 56.1% | Claude Opus 4.8 leads |
| AA Coding IndexSource | 74.3% | — | Not comparable |
| AA-SciCodeSource | 53.5% | — | Not comparable |
| FrontierCode 1.1 MainSource | 46.5% | — | Not comparable |
Reasoning2 benchmarks
Knowledge10 benchmarks
| Benchmark | Claude Opus 4.8 | Composer 2.5 | Result |
|---|---|---|---|
| GPQASource | 93.6% | — | Not comparable |
| GPQA-DSource | 93.6% | — | Not comparable |
| HLESource | 57.9% | — | Not comparable |
| HLE w/o toolsSource | 49.8% | — | Not comparable |
| Artificial Analysis Intelligence IndexSource | 55.7% | — | Not comparable |
| AA-GPQA DiamondSource | 92.0% | — | Not comparable |
| AA-HLESource | 45.7% | — | Not comparable |
| AA-Omniscience IndexSource | 27.4% | — | Not comparable |
| AA-Omniscience AccuracySource | 46.6% | — | Not comparable |
| AA-Omniscience Hallucination RateSource | 35.9% | — | Not comparable |
Math3 benchmarks
Multilingual1 benchmarks
| Benchmark | Claude Opus 4.8 | Composer 2.5 | Result |
|---|---|---|---|
| INCLUDESource | 87.6% | — | Not comparable |
Multimodal5 benchmarks
Inst. Following1 benchmarks
| Benchmark | Claude Opus 4.8 | Composer 2.5 | Result |
|---|---|---|---|
| AA-IFBenchSource | 62.2% | — | Not comparable |
Frequently Asked Questions (2)
Which is better, Claude Opus 4.8 or Composer 2.5?
Claude Opus 4.8 and Composer 2.5 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 agentic tasks, Claude Opus 4.8 or Composer 2.5?
Claude Opus 4.8 has the edge for agentic tasks in this comparison, averaging 80.3 versus 69.3. Inside this category, Terminal-Bench 2.0 is the benchmark that creates the most daylight between them.
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