# Claude Sonnet 4.5 Thinking vs Mercury 2

> Side-by-side benchmark comparison for Claude Sonnet 4.5 Thinking and Mercury 2 across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/claude-sonnet-4-5-thinking-vs-mercury-2
- Last updated: September 4, 2026

- Shared sourced benchmarks: 0
- HTML indexing: indexable
- Ranking lane: BenchAlign v5

## Quick Verdict

No benchmark verdict yet: there is no shared sourced benchmark row for Claude Sonnet 4.5 Thinking and Mercury 2.

## Summary

- Claude Sonnet 4.5 Thinking and Mercury 2 do not currently share a sourced benchmark row. The mirror therefore compares metadata, pricing, context windows, and each model's separately reported coverage without naming a benchmark winner.

## Model Snapshot

| Property | Claude Sonnet 4.5 Thinking | Mercury 2 |
|----------|----------|----------|
| Creator | Anthropic | Inception |
| Type | Proprietary | Proprietary |
| Reasoning | Reasoning | Reasoning |
| Context | 200K | 128K |
| Independent public score (not head-to-head) | null | 47.28 |
| Benchmarks Covered | 1 | 0 |
| Pricing (input/output) | N/A | $0.25 / $0.75 |

## Category Breakdown

### Agentic

- Winner: Insufficient shared evidence
- Claude Sonnet 4.5 Thinking public-lane score: Coming soon
- Mercury 2 public-lane score: 42.7 (Estimated · #112/151)

### Coding

- Winner: Insufficient shared evidence
- Claude Sonnet 4.5 Thinking public-lane score: Coming soon
- Mercury 2 public-lane score: 25.5 (Supported · #177/183)

| Benchmark | Claude Sonnet 4.5 Thinking | Mercury 2 | Winner |
|-----------|-----------|-----------|--------|
| Vibe Code Bench | 22.62% | Coming soon | Coming soon |

## FAQ

### Can I compare Claude Sonnet 4.5 Thinking and Mercury 2 on BenchLM yet?

Not fully yet. BenchLM is tracking both models, but sourced benchmark coverage is still incomplete for a fair score-level comparison.

### Why does this page show "coming soon" values?

BenchLM only calls winners when public benchmark coverage is available on both sides of the comparison.

## Related Comparisons

- [Claude Sonnet 4.5 Thinking vs Claude Sonnet 4.5](/compare/claude-sonnet-4-5-vs-claude-sonnet-4-5-thinking)
- [Mercury 2 vs Claude Sonnet 4.5](/compare/claude-sonnet-4-5-vs-mercury-2)
- [Claude Sonnet 4.5 Thinking vs Claude Fable 5.1](/compare/claude-fable-5-1-vs-claude-sonnet-4-5-thinking)
- [Mercury 2 vs Claude Fable 5.1](/compare/claude-fable-5-1-vs-mercury-2)

## Explore More

- [Claude Sonnet 4.5 Thinking profile](/models/claude-sonnet-4-5-thinking)
- [Mercury 2 profile](/models/mercury-2)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)