# Longcat Flash Chat vs Mercury 2.5

> Longcat Flash Chat is the stronger model overall, scoring 42.1 to 33.5 on the Noometry Index.

- Canonical page: https://noometry.com/compare/longcat-flash-chat-vs-mercury-2-5
- Last updated: 2026-10-11
- Shared benchmarks: 0

## Summary

- The widest gap is in math, where Longcat Flash Chat leads 39.4 to 23.3.
- Longcat Flash Chat has downloadable open weights; the other is API-only.

## Snapshot

| | Longcat Flash Chat | Mercury 2.5 |
|---|---|---|
| Provider | Meituan | Inception |
| Noometry Index | 42.1 | 33.5 |
| Rank | 120 | 242 |
| Context | — | 260K |
| Input $/M | — | $0.04 |
| Output $/M | — | $0.15 |
| Weights | Open | Proprietary |

## Coding

- Longcat Flash Chat: 43.5 (#87)
- Mercury 2.5: 39.5 (#156)

| Benchmark | Longcat Flash Chat | Mercury 2.5 |
|---|---|---|
| SciCode | — | 38.5% |
| LMArena Coding | 1471 | — |
| ALE-Bench | — | 301.65 |

## Reasoning

- Longcat Flash Chat: 19.0 (#272)
- Mercury 2.5: 22.4 (#193)

| Benchmark | Longcat Flash Chat | Mercury 2.5 |
|---|---|---|
| Kagi LLM Benchmark | 43.9% | — |
| NYT Connections (extended) | 17.7% | — |
| CritPt | — | 0% |
| LMArena Hard Prompts | 1440 | — |

## Math

- Longcat Flash Chat: 39.4 (#107)
- Mercury 2.5: 23.3 (#272)

| Benchmark | Longcat Flash Chat | Mercury 2.5 |
|---|---|---|
| ProofBench | — | 3% |
| LMArena Math | 1442 | — |

## Knowledge

- Longcat Flash Chat: 40.6 (#116)
- Mercury 2.5: —

| Benchmark | Longcat Flash Chat | Mercury 2.5 |
|---|---|---|
| LMArena Expert | 1454 | — |

## Multilingual

- Longcat Flash Chat: 51.9 (#101)
- Mercury 2.5: —

| Benchmark | Longcat Flash Chat | Mercury 2.5 |
|---|---|---|
| LMArena Non-English | 1404 | — |
| LMArena Chinese | 1465 | — |
| LMArena French | 1456 | — |
| LMArena German | 1408 | — |
| LMArena Japanese | 1373 | — |
| LMArena Korean | 1371 | — |
| LMArena Russian | 1395 | — |
| LMArena Spanish | 1445 | — |

## Instruction Following

- Longcat Flash Chat: 74.4 (#96)
- Mercury 2.5: —

| Benchmark | Longcat Flash Chat | Mercury 2.5 |
|---|---|---|
| LMArena Instruction Following | 1411 | — |

## Long Context

- Longcat Flash Chat: 43.5 (#93)
- Mercury 2.5: —

| Benchmark | Longcat Flash Chat | Mercury 2.5 |
|---|---|---|
| LMArena Longer Query | 1425 | — |

## Writing & Preference

- Longcat Flash Chat: 61.0 (#91)
- Mercury 2.5: —

| Benchmark | Longcat Flash Chat | Mercury 2.5 |
|---|---|---|
| LMArena Text | 1427 | — |
| LMArena Creative Writing | 1388 | — |
| LMArena Multi-Turn | 1418 | — |

## FAQ

### Is Longcat Flash Chat better than Mercury 2.5?

Longcat Flash Chat is the stronger model overall, scoring 42.1 to 33.5 on the Noometry Index.

### Is Longcat Flash Chat or Mercury 2.5 better for coding?

Longcat Flash Chat scores higher on coding benchmarks: 43.5 versus 39.5 in the Noometry coding category.

### How many benchmarks do Longcat Flash Chat and Mercury 2.5 share?

0 benchmarks have published results for both models. Longcat Flash Chat has 19 scored results on Noometry and Mercury 2.5 has 4.