# Hy4 preview vs Mercury 2.5

> Side-by-side benchmark comparison for Hy4 preview and Mercury 2.5 across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/hy4-preview-vs-mercury-2-5
- Last updated: September 8, 2026

- Shared sourced benchmarks: 1
- HTML indexing: indexable
- Ranking lane: BenchAlign v5

## Quick Verdict

Evidence is too thin for a benchmark verdict: Hy4 preview and Mercury 2.5 share only 1 sourced benchmark row.

## Summary

- Only 1 shared sourced benchmark row is available. That is not enough for a broad capability verdict, so this mirror does not name an overall winner.
- Hy4 preview has the lower published output-token price.
- Hy4 preview has the larger published context window at 1M.

## Model Snapshot

| Property | Hy4 preview | Mercury 2.5 |
|----------|----------|----------|
| Creator | Tencent | Inception |
| Type | Open Weight | Proprietary |
| Reasoning | Reasoning | Reasoning |
| Context | 1M | 260K |
| Independent public score (not head-to-head) | 61.03 | null |
| Benchmarks Covered | 28 | 5 |
| Pricing (input/output) | $0.00 / $0.00 | $0.04 / $0.15 |

## Category Breakdown

### Agentic

- Winner: Insufficient shared evidence
- Hy4 preview public-lane score: 58.6 (Estimated · #30/152)
- Mercury 2.5 public-lane score: 44.5 (Estimated · #91/152)

| Benchmark | Hy4 preview | Mercury 2.5 | Winner |
|-----------|-----------|-----------|--------|
| Terminal-Bench 2.1 | 85.4% | Coming soon | Coming soon |
| CyberGym | 78.4% | Coming soon | Coming soon |
| WideResearch | 83.9% | Coming soon | Coming soon |
| DRACO | 77.2% | Coming soon | Coming soon |
| MCP Atlas | 83.7% | Coming soon | Coming soon |
| Toolathlon-Verified | 74.1% | Coming soon | Coming soon |
| APEX-Agents | 37.1% | Coming soon | Coming soon |
| skillsBench | 62.9% | Coming soon | Coming soon |
| JobBench | 61.7% | Coming soon | Coming soon |
| Agents' Last Exam | 22.8% | Coming soon | Coming soon |
| AutomationBench | 32.1% | Coming soon | Coming soon |
| BankerToolBench | 78.6% | Coming soon | Coming soon |
| HLE w/ tools | 55.4% | Coming soon | Coming soon |
| τ³-bench results | Coming soon | 96.0% | Coming soon |
| DeepSearchQA | Coming soon | 34.0% | Coming soon |

### Coding

- Winner: Insufficient shared evidence
- Hy4 preview public-lane score: 59.6 (Estimated · #24/151)
- Mercury 2.5 public-lane score: 47.8 (Estimated · #73/151)

| Benchmark | Hy4 preview | Mercury 2.5 | Winner |
|-----------|-----------|-----------|--------|
| Terminal-Bench 2.1 | 85.4% | Coming soon | Coming soon |
| SWE-bench Pro | 65.7% | Coming soon | Coming soon |
| SWE Multilingual | 82.9% | Coming soon | Coming soon |
| deepSwe | 64.3% | Coming soon | Coming soon |
| NL2Repo | 58.9% | Coming soon | Coming soon |
| ProgramBench | 17.5% | Coming soon | Coming soon |
| PostTrain Bench | 35.6% | Coming soon | Coming soon |
| sweMarathon | 31.9% | Coming soon | Coming soon |
| SciCode | Coming soon | 38% | Coming soon |

### Multimodal & Grounded

- Winner: Insufficient shared evidence
- Hy4 preview public-lane score: 84.8 (Unranked · 1 rankable row)
- Mercury 2.5 public-lane score: Coming soon

| Benchmark | Hy4 preview | Mercury 2.5 | Winner |
|-----------|-----------|-----------|--------|
| OfficeQA Pro | 66.2% | Coming soon | Coming soon |

### Reasoning

- Winner: Insufficient shared evidence
- Hy4 preview public-lane score: Coming soon
- Mercury 2.5 public-lane score: 67.7 (Unranked · 1 rankable row)

| Benchmark | Hy4 preview | Mercury 2.5 | Winner |
|-----------|-----------|-----------|--------|
| CritPt | 16.9% | Coming soon | Coming soon |

### Knowledge

- Winner: Insufficient shared evidence
- Hy4 preview public-lane score: 57 (Estimated · #46/182)
- Mercury 2.5 public-lane score: 48.3 (Estimated · #94/182)

| Benchmark | Hy4 preview | Mercury 2.5 | Winner |
|-----------|-----------|-----------|--------|
| GPQA | 92.3% | Coming soon | Coming soon |
| GPQA-D | 92.3% | 79.0% | Hy4 preview |
| HLE | 55.4% | Coming soon | Coming soon |
| HLE w/o tools | 43.4% | Coming soon | Coming soon |

### Instruction Following

- Winner: Insufficient shared evidence
- Hy4 preview public-lane score: Coming soon
- Mercury 2.5 public-lane score: 80.1 (#53/121)

| Benchmark | Hy4 preview | Mercury 2.5 | Winner |
|-----------|-----------|-----------|--------|
| IFBench | Coming soon | 77% | Coming soon |

### Mathematics

- Winner: Insufficient shared evidence
- Hy4 preview public-lane score: Coming soon
- Mercury 2.5 public-lane score: Coming soon

| Benchmark | Hy4 preview | Mercury 2.5 | Winner |
|-----------|-----------|-----------|--------|
| Apex | 74.2% | Coming soon | Coming soon |

## FAQ

### Is there enough evidence to pick between Hy4 preview and Mercury 2.5?

Not yet. The models share only 1 sourced benchmark row, so this mirror reports the available measurements and metadata without naming a broad winner.

### What can I compare safely on this page?

Published pricing, context windows, model type, and individual shared benchmark rows are directly comparable. Independent overall scores and non-overlapping benchmark coverage are labeled separately and should not be read as a controlled head-to-head result.

## Related Comparisons

- [Hy4 preview vs Mercury 2.5 Preview](/compare/hy4-preview-vs-mercury-2-5-preview)
- [Mercury 2.5 vs Mercury 2.5 Preview](/compare/mercury-2-5-vs-mercury-2-5-preview)
- [Hy4 preview vs Claude Fable 5.1](/compare/claude-fable-5-1-vs-hy4-preview)
- [Mercury 2.5 vs Claude Fable 5.1](/compare/claude-fable-5-1-vs-mercury-2-5)

## Explore More

- [Hy4 preview profile](/models/hy4-preview)
- [Mercury 2.5 profile](/models/mercury-2-5)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)