# Mercury 2 vs Mercury 2.5

> Mercury 2 has enough public results to be ranked (#167); Mercury 2.5 does not yet, so treat this comparison as directional.

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

## Summary

- They share 1 benchmark with published results for both.
- Mercury 2.5 is cheaper at $0.04 / $0.15 per million input/output tokens, against $0.25 / $0.75 for Mercury 2.
- Mercury 2.5 accepts more context: 260K tokens versus 128K.

## Snapshot

| | Mercury 2 | Mercury 2.5 |
|---|---|---|
| Provider | Inception | Inception |
| Noometry Index | 38.8 | 30.2 |
| Rank | 167 | — |
| Context | 128K | 260K |
| Input $/M | $0.25 | $0.04 |
| Output $/M | $0.75 | $0.15 |
| Weights | Proprietary | Proprietary |

## Coding

- Mercury 2: 33.2 (#250)
- Mercury 2.5: —

| Benchmark | Mercury 2 | Mercury 2.5 |
|---|---|---|
| ALE-Bench | 785.58 | 301.65 |
| LMArena WebDev | 1170 | — |
| SciCode | 38.7% | — |
| WeirdML | 43.2% | — |
| LMArena Coding | 1391 | — |

## Reasoning

- Mercury 2: 23.0 (#170)
- Mercury 2.5: —

| Benchmark | Mercury 2 | Mercury 2.5 |
|---|---|---|
| CritPt | 0.8% | — |
| LMArena Hard Prompts | 1362 | — |

## Math

- Mercury 2: —
- Mercury 2.5: 22.4

| Benchmark | Mercury 2 | Mercury 2.5 |
|---|---|---|
| ProofBench | — | 3% |

## Knowledge

- Mercury 2: 35.6 (#170)
- Mercury 2.5: —

| Benchmark | Mercury 2 | Mercury 2.5 |
|---|---|---|
| Vectara Hallucination Rate | 12.3% | — |
| LMArena Expert | 1358 | — |

## Multilingual

- Mercury 2: 46.8 (#153)
- Mercury 2.5: —

| Benchmark | Mercury 2 | Mercury 2.5 |
|---|---|---|
| LMArena Non-English | 1331 | — |
| LMArena Chinese | 1416 | — |
| LMArena Russian | 1303 | — |

## Instruction Following

- Mercury 2: 70.4 (#161)
- Mercury 2.5: —

| Benchmark | Mercury 2 | Mercury 2.5 |
|---|---|---|
| LMArena Instruction Following | 1328 | — |

## Long Context

- Mercury 2: 40.4 (#149)
- Mercury 2.5: —

| Benchmark | Mercury 2 | Mercury 2.5 |
|---|---|---|
| LMArena Longer Query | 1329 | — |

## Writing & Preference

- Mercury 2: 54.0 (#151)
- Mercury 2.5: —

| Benchmark | Mercury 2 | Mercury 2.5 |
|---|---|---|
| LMArena Text | 1355 | — |
| LMArena Creative Writing | 1289 | — |
| LMArena Multi-Turn | 1358 | — |

## FAQ

### Is Mercury 2 better than Mercury 2.5?

Mercury 2 has enough public results to be ranked (#167); Mercury 2.5 does not yet, so treat this comparison as directional.

### Which is cheaper, Mercury 2 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; Mercury 2 lists at $0.25 and $0.75.

### Which has the bigger context window?

Mercury 2.5 does, with 260K tokens against 128K.

### How many benchmarks do Mercury 2 and Mercury 2.5 share?

1 benchmark has published results for both models. Mercury 2 has 17 scored results on Noometry and Mercury 2.5 has 2.