# Hy4 preview vs Mercury 2.5

> Hy4 preview is the stronger model overall, scoring 45.3 to 33.5 on the Noometry Index. Mercury 2.5 costs 19× less per token, which makes it the better buy when Hy4 preview's lead doesn't matter for your workload.

- Canonical page: https://noometry.com/compare/hy4-preview-vs-mercury-2-5
- Last updated: 2026-10-12
- Shared benchmarks: 1

## Summary

- They share 1 benchmark with published results for both. Hy4 preview scores higher in 3 categories and Mercury 2.5 in 0 categories; 3 gaps are clear of the uncertainty.
- The widest gap is in math, where Hy4 preview leads 55.7 to 23.3.
- The biggest single-benchmark swing is ProofBench: 75% for Hy4 preview and 3% for Mercury 2.5.
- Mercury 2.5 is cheaper at $0.04 / $0.15 per million input/output tokens, against $0.83 / $2.50 for Hy4 preview.
- Hy4 preview accepts more context: 1.05M tokens versus 260K.
- Hy4 preview has downloadable open weights; the other is API-only.

## Snapshot

| | Hy4 preview | Mercury 2.5 |
|---|---|---|
| Provider | Tencent | Inception |
| Noometry Index | 45.3 | 33.5 |
| Rank | 73 | 242 |
| Context | 1.05M | 260K |
| Input $/M | $0.83 | $0.04 |
| Output $/M | $2.50 | $0.15 |
| Weights | Open | Proprietary |

## Coding

- Hy4 preview: 51.6 (#38)
- Mercury 2.5: 39.5 (#156)

| Benchmark | Hy4 preview | Mercury 2.5 |
|---|---|---|
| LMArena WebDev | 1632 | — |
| SciCode | — | 38.5% |
| ALE-Bench | — | 301.65 |

## Reasoning

- Hy4 preview: 31.9 (#79)
- Mercury 2.5: 22.4 (#193)

| Benchmark | Hy4 preview | Mercury 2.5 |
|---|---|---|
| NYT Connections (extended) | 68.2% | — |
| CritPt | — | 0% |

## Math

- Hy4 preview: 55.7 (#42)
- Mercury 2.5: 23.3 (#272)

| Benchmark | Hy4 preview | Mercury 2.5 |
|---|---|---|
| ProofBench | 75% | 3% |

## FAQ

### Is Hy4 preview better than Mercury 2.5?

Hy4 preview is the stronger model overall, scoring 45.3 to 33.5 on the Noometry Index. Mercury 2.5 costs 19× less per token, which makes it the better buy when Hy4 preview's lead doesn't matter for your workload.

### Which is cheaper, Hy4 preview or Mercury 2.5?

Mercury 2.5 is cheaper. It lists at $0.04 per million input tokens and $0.15 per million output tokens; Hy4 preview lists at $0.83 and $2.50.

### Is Hy4 preview or Mercury 2.5 better for coding?

Hy4 preview scores higher on coding benchmarks: 51.6 versus 39.5 in the Noometry coding category.

### Which has the bigger context window?

Hy4 preview does, with 1.05M tokens against 260K.

### How many benchmarks do Hy4 preview and Mercury 2.5 share?

1 benchmark has published results for both models. Hy4 preview has 3 scored results on Noometry and Mercury 2.5 has 4.