Model comparison
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.
Last verified . 1 shared benchmarks.
TencentSummary
- 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.
Side by side
| Hy4 preview | Mercury 2.5 | |
|---|---|---|
| Provider | Tencent | Inception |
| Noometry Index | 45.3 | 33.5 |
| Released | 2026-08-28 | 2026-09-08 |
| Weights | Open | Proprietary |
| Context window | 1.05M | 260K |
| Max output | 64K | 66K |
| Input $ / M tokens | $0.83 | $0.04 |
| Output $ / M tokens | $2.50 | $0.15 |
| Results tracked | 3 | 4 |
Sponsored placements are available on pages like this one. Advertise on Noometry
Category by category
Coding Hy4 preview leads
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 leads
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 leads
Hy4 preview: 55.7 (#42), Mercury 2.5: 23.3 (#272)
| Benchmark | Hy4 preview | Mercury 2.5 |
|---|---|---|
| ProofBench | 75% | 3% |
Frequently asked questions
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.