# DeepSeek-V3.1-Terminus vs Mercury

> DeepSeek-V3.1-Terminus is the stronger model overall, scoring 42.6 to 37.3 on the Noometry Index.

- Canonical page: https://noometry.com/compare/deepseek-v3-1-terminus-vs-mercury
- Last updated: 2026-10-10
- Shared benchmarks: 9

## Summary

- They share 9 benchmarks with published results for both. DeepSeek-V3.1-Terminus scores higher in 6 categories and Mercury in 0 categories; 6 gaps are clear of the uncertainty.
- The widest gap is in writing & preference, where DeepSeek-V3.1-Terminus leads 61.3 to 46.2.
- The biggest single-benchmark swing is Kagi LLM Benchmark: 57.4% for DeepSeek-V3.1-Terminus and 21.6% for Mercury.
- DeepSeek-V3.1-Terminus has downloadable open weights; the other is API-only.

## Snapshot

| | DeepSeek-V3.1-Terminus | Mercury |
|---|---|---|
| Provider | DeepSeek | Inception |
| Noometry Index | 42.6 | 37.3 |
| Rank | 96 | 192 |
| Context | 164K | — |
| Input $/M | $0.30 | — |
| Output $/M | $1 | — |
| Weights | Open | Proprietary |

## Coding

- DeepSeek-V3.1-Terminus: 41.5 (#114)
- Mercury: 38.1 (#164)

| Benchmark | DeepSeek-V3.1-Terminus | Mercury |
|---|---|---|
| LMArena Coding | 1426 | 1323 |
| SciCode | 40.6% | — |
| ALE-Bench | 745.17 | — |

## Reasoning

- DeepSeek-V3.1-Terminus: 25.7 (#126)
- Mercury: 16.8 (#288)

| Benchmark | DeepSeek-V3.1-Terminus | Mercury |
|---|---|---|
| Kagi LLM Benchmark | 57.4% | 21.6% |
| LMArena Hard Prompts | 1427 | 1284 |
| CritPt | 1.7% | — |
| DTBench | 81.3% | — |
| LMCA | 28.6% | — |

## Math

- DeepSeek-V3.1-Terminus: 35.7 (#138)
- Mercury: —

| Benchmark | DeepSeek-V3.1-Terminus | Mercury |
|---|---|---|
| LMArena Math | 1402 | — |

## Multilingual

- DeepSeek-V3.1-Terminus: 52.3 (#87)
- Mercury: 41.7 (#201)

| Benchmark | DeepSeek-V3.1-Terminus | Mercury |
|---|---|---|
| LMArena Non-English | 1407 | 1259 |
| LMArena Russian | 1434 | — |

## Instruction Following

- DeepSeek-V3.1-Terminus: 74.4 (#96)
- Mercury: 65.3 (#220)

| Benchmark | DeepSeek-V3.1-Terminus | Mercury |
|---|---|---|
| LMArena Instruction Following | 1406 | 1238 |

## Long Context

- DeepSeek-V3.1-Terminus: 43.5 (#88)
- Mercury: 38.3 (#193)

| Benchmark | DeepSeek-V3.1-Terminus | Mercury |
|---|---|---|
| LMArena Longer Query | 1426 | 1264 |

## Writing & Preference

- DeepSeek-V3.1-Terminus: 61.3 (#87)
- Mercury: 46.2 (#216)

| Benchmark | DeepSeek-V3.1-Terminus | Mercury |
|---|---|---|
| LMArena Text | 1420 | 1282 |
| LMArena Creative Writing | 1404 | 1186 |
| LMArena Multi-Turn | 1411 | 1283 |

## FAQ

### Is DeepSeek-V3.1-Terminus better than Mercury?

DeepSeek-V3.1-Terminus is the stronger model overall, scoring 42.6 to 37.3 on the Noometry Index.

### Is DeepSeek-V3.1-Terminus or Mercury better for coding?

DeepSeek-V3.1-Terminus scores higher on coding benchmarks: 41.5 versus 38.1 in the Noometry coding category.

### How many benchmarks do DeepSeek-V3.1-Terminus and Mercury share?

9 benchmarks have published results for both models. DeepSeek-V3.1-Terminus has 16 scored results on Noometry and Mercury has 9.