Model comparison
Claude Sonnet 5 vs Mercury 2
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 Sonnet 5 #29 (Estimated); Mercury 2 #105 (Supported). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. Claude Sonnet 5 and Mercury 2 share 0 comparable benchmark results. 0 of 8 categories are comparable. 36 results are unique to Claude Sonnet 5; 0 to Mercury 2.
Updated July 23, 2026- Shared results
- 0
- Claude Sonnet 5 only
- 36
- Mercury 2 only
- 0
- Comparable categories
- 0 / 8
Benchmark data for Claude Sonnet 5 and Mercury 2 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 does not have sourced benchmark coverage for Mercury 2 yet. This comparison is currently limited to metadata such as context window, reasoning mode, and pricing where available.
Claude Sonnet 5 is priced at $2.00 input / $10.00 output per 1M tokens, versus $0.25 input / $0.75 output per 1M tokens for Mercury 2. Claude Sonnet 5 has the larger context window at 1M, compared with 128K for Mercury 2.
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | Claude Sonnet 5 | Mercury 2 | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | Claude Sonnet 5$2 input / $10 output | Mercury 2$0.25 input / $0.75 output | Mercury 2 has the lower combined listed price. |
| Generation speedtokens per second | Claude Sonnet 5Not available | Mercury 2789 tok/s | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | Claude Sonnet 5Not available | Mercury 23.88 s | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | Claude Sonnet 51M | Mercury 2128K | Claude Sonnet 5 lists the larger context window. |
Benchmark Deep Dive
Agentic13 benchmarks
| Benchmark | Claude Sonnet 5 | Mercury 2 | Result |
|---|---|---|---|
| Terminal-Bench 2.0Source | 80.4% | — | Not comparable |
| BrowseCompSource | 84.7% | — | Not comparable |
| HLE w/ toolsSource | 57.4% | — | Not comparable |
| OSWorld-VerifiedSource | 81.2% | — | Not comparable |
| GDPval-AASource | 1607 | — | Not comparable |
| AA Agentic IndexSource | 46.7% | — | Not comparable |
| GDPval-AASource | 55.4% | — | Not comparable |
| AA BriefcaseSource | 1388 | — | Not comparable |
| AA AutomationBenchSource | 39.2% | — | Not comparable |
| AA EnterpriseOps-GymSource | 44.7% | — | Not comparable |
| AA Harvey LABSource | 90.1% | — | Not comparable |
| AA Tau3 BankingSource | 28.2% | — | Not comparable |
| aaTerminalBench21Source | 80.5% | — | Not comparable |
Coding9 benchmarks
| Benchmark | Claude Sonnet 5 | Mercury 2 | Result |
|---|---|---|---|
| SWE-bench VerifiedSource | 85.2% | — | Not comparable |
| SWE-bench ProSource | 63.2% | — | Not comparable |
| SWE MultilingualSource | 78.3% | — | Not comparable |
| SWE MultimodalSource | 28.1% | — | Not comparable |
| Terminal-Bench 2.0Source | 80.4% | — | Not comparable |
| FrontierCode 1.1 MainSource | 42.7% | — | Not comparable |
| cursorBench32Source | 61.5% | — | Not comparable |
| AA Coding IndexSource | 71.5% | — | Not comparable |
| AA-SciCodeSource | 53.6% | — | Not comparable |
Reasoning2 benchmarks
Knowledge8 benchmarks
| Benchmark | Claude Sonnet 5 | Mercury 2 | Result |
|---|---|---|---|
| HLESource | 57.4% | — | Not comparable |
| HLE w/o toolsSource | 43.2% | — | Not comparable |
| Artificial Analysis Intelligence IndexSource | 53.4% | — | Not comparable |
| AA-GPQA DiamondSource | 91.1% | — | Not comparable |
| AA-HLESource | 39.6% | — | Not comparable |
| AA-Omniscience IndexSource | 15.3% | — | Not comparable |
| AA-Omniscience AccuracySource | 38.3% | — | Not comparable |
| AA-Omniscience Hallucination RateSource | 37.3% | — | Not comparable |
Frequently Asked Questions (3)
Can I compare Claude Sonnet 5 and Mercury 2 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 5 and Mercury 2 today?
Claude Sonnet 5: $2.00 input / $10.00 output per 1M tokens Mercury 2: $0.25 input / $0.75 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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