# DeepSeek-V2.5 (Sep 2024) vs gpt-oss-20b

> DeepSeek-V2.5 (Sep 2024) is the stronger model overall, scoring 37.0 to 32.1 on the Noometry Index.

- Canonical page: https://noometry.com/compare/deepseek-v2-5-vs-gpt-oss-20b
- Last updated: 2026-10-10
- Shared benchmarks: 16

## Summary

- They share 16 benchmarks with published results for both. DeepSeek-V2.5 (Sep 2024) scores higher in 5 categories and gpt-oss-20b in 3 categories; 6 gaps are clear of the uncertainty.
- The widest gap is in writing & preference, where DeepSeek-V2.5 (Sep 2024) leads 50.0 to 35.8.

## Snapshot

| | DeepSeek-V2.5 (Sep 2024) | gpt-oss-20b |
|---|---|---|
| Provider | DeepSeek | OpenAI |
| Noometry Index | 37.0 | 32.1 |
| Rank | 197 | 249 |
| Context | — | 131K |
| Input $/M | — | $0.018 |
| Output $/M | — | $0.09 |
| Weights | Open | Open |

## Coding

- DeepSeek-V2.5 (Sep 2024): 31.3 (#274)
- gpt-oss-20b: 37.1 (#185)

| Benchmark | DeepSeek-V2.5 (Sep 2024) | gpt-oss-20b |
|---|---|---|
| LMArena Coding | 1310 | 1307 |
| Aider Polyglot | 17.8% | — |
| SciCode | — | 34.4% |
| WeirdML | — | 40.9% |
| BigCodeBench Instruct | 48.6% | — |
| BigCodeBench Complete | 53.2% | — |
| ALE-Bench | — | 566.05 |
| HumanEval+ | 83.5% | — |
| MBPP+ | 74.1% | — |

## Agentic & Tool Use

- DeepSeek-V2.5 (Sep 2024): —
- gpt-oss-20b: 9.2 (#146)

| Benchmark | DeepSeek-V2.5 (Sep 2024) | gpt-oss-20b |
|---|---|---|
| Terminal-Bench | — | 3.4% |

## Reasoning

- DeepSeek-V2.5 (Sep 2024): 24.5 (#145)
- gpt-oss-20b: 18.8 (#251)

| Benchmark | DeepSeek-V2.5 (Sep 2024) | gpt-oss-20b |
|---|---|---|
| LMArena Hard Prompts | 1289 | 1274 |
| Kagi LLM Benchmark | — | 53.2% |
| CritPt | — | 1.4% |
| Chess Puzzles | — | 4% |
| DTBench | — | 68% |
| LMCA | — | 14.5% |
| Epoch Capabilities Index | — | 137.81 |

## Math

- DeepSeek-V2.5 (Sep 2024): 33.3 (#177)
- gpt-oss-20b: 37.6 (#93)

| Benchmark | DeepSeek-V2.5 (Sep 2024) | gpt-oss-20b |
|---|---|---|
| LMArena Math | 1289 | 1317 |
| OTIS Mock AIME 2024-2025 | — | 65.3% |
| Omni-MATH | — | 56.5% |

## Knowledge

- DeepSeek-V2.5 (Sep 2024): 34.2 (#190)
- gpt-oss-20b: 34.6 (#186)

| Benchmark | DeepSeek-V2.5 (Sep 2024) | gpt-oss-20b |
|---|---|---|
| LMArena Expert | 1266 | 1258 |
| GPQA Diamond | — | 60.8% |
| MMLU-Pro | — | 74% |
| GPQA (HELM) | — | 59.4% |

## Multilingual

- DeepSeek-V2.5 (Sep 2024): 42.7 (#188)
- gpt-oss-20b: 42.4 (#192)

| Benchmark | DeepSeek-V2.5 (Sep 2024) | gpt-oss-20b |
|---|---|---|
| LMArena Non-English | 1273 | 1269 |
| LMArena Chinese | 1317 | 1311 |
| LMArena German | 1258 | 1249 |
| LMArena Japanese | 1228 | 1245 |
| LMArena Korean | 1209 | 1239 |
| LMArena Russian | 1289 | 1279 |
| LMArena Spanish | 1248 | 1267 |
| LMArena French | 1288 | — |

## Instruction Following

- DeepSeek-V2.5 (Sep 2024): 67.7 (#189)
- gpt-oss-20b: 62.0 (#235)

| Benchmark | DeepSeek-V2.5 (Sep 2024) | gpt-oss-20b |
|---|---|---|
| LMArena Instruction Following | 1280 | 1236 |
| IFEval | — | 73.2% |

## Long Context

- DeepSeek-V2.5 (Sep 2024): 39.5 (#169)
- gpt-oss-20b: 37.9 (#203)

| Benchmark | DeepSeek-V2.5 (Sep 2024) | gpt-oss-20b |
|---|---|---|
| LMArena Longer Query | 1301 | 1251 |

## Writing & Preference

- DeepSeek-V2.5 (Sep 2024): 50.0 (#182)
- gpt-oss-20b: 35.8 (#260)

| Benchmark | DeepSeek-V2.5 (Sep 2024) | gpt-oss-20b |
|---|---|---|
| LMArena Text | 1294 | 1288 |
| LMArena Creative Writing | 1285 | 1201 |
| LMArena Multi-Turn | 1297 | 1268 |
| EQ-Bench Creative Writing | — | 666 |
| WildBench | — | 73.7% |

## FAQ

### Is DeepSeek-V2.5 (Sep 2024) better than gpt-oss-20b?

DeepSeek-V2.5 (Sep 2024) is the stronger model overall, scoring 37.0 to 32.1 on the Noometry Index.

### Is DeepSeek-V2.5 (Sep 2024) or gpt-oss-20b better for coding?

gpt-oss-20b scores higher on coding benchmarks: 37.1 versus 31.3 in the Noometry coding category.

### How many benchmarks do DeepSeek-V2.5 (Sep 2024) and gpt-oss-20b share?

16 benchmarks have published results for both models. DeepSeek-V2.5 (Sep 2024) has 22 scored results on Noometry and gpt-oss-20b has 34.