# DeepSeek-V2.5 (Sep 2024) vs GPT-5.5 Instant

> GPT-5.5 Instant is the stronger model overall, scoring 42.7 to 37.6 on the Noometry Index.

- Canonical page: https://noometry.com/compare/deepseek-v2-5-vs-gpt-5-5-instant
- Last updated: 2026-10-12
- Shared benchmarks: 17

## Summary

- They share 17 benchmarks with published results for both. DeepSeek-V2.5 (Sep 2024) scores higher in 2 categories and GPT-5.5 Instant in 6 categories; 7 gaps are clear of the uncertainty.
- The widest gap is in knowledge, where GPT-5.5 Instant leads 48.9 to 34.8.
- DeepSeek-V2.5 (Sep 2024) has downloadable open weights; the other is API-only.

## Snapshot

| | DeepSeek-V2.5 (Sep 2024) | GPT-5.5 Instant |
|---|---|---|
| Provider | DeepSeek | OpenAI |
| Noometry Index | 37.6 | 42.7 |
| Rank | 200 | 110 |
| Context | — | — |
| Input $/M | — | — |
| Output $/M | — | — |
| Weights | Open | Proprietary |

## Coding

- DeepSeek-V2.5 (Sep 2024): 31.7 (#281)
- GPT-5.5 Instant: 44.3 (#74)

| Benchmark | DeepSeek-V2.5 (Sep 2024) | GPT-5.5 Instant |
|---|---|---|
| LMArena Coding | 1309 | 1433 |
| Aider Polyglot | 17.8% | — |
| SciCode | — | 48.6% |
| BigCodeBench Instruct | 48.6% | — |
| BigCodeBench Complete | 53.2% | — |
| HumanEval+ | 83.5% | — |
| MBPP+ | 74.1% | — |

## Reasoning

- DeepSeek-V2.5 (Sep 2024): 25.6 (#145)
- GPT-5.5 Instant: 24.9 (#155)

| Benchmark | DeepSeek-V2.5 (Sep 2024) | GPT-5.5 Instant |
|---|---|---|
| LMArena Hard Prompts | 1289 | 1426 |
| CritPt | — | 0% |
| Chess Puzzles | — | 12% |
| Epoch Capabilities Index | — | 142.52 |

## Math

- DeepSeek-V2.5 (Sep 2024): 35.9 (#177)
- GPT-5.5 Instant: 26.5 (#259)

| Benchmark | DeepSeek-V2.5 (Sep 2024) | GPT-5.5 Instant |
|---|---|---|
| LMArena Math | 1288 | 1420 |
| FrontierMath (Tiers 1-3) | — | 26.3% |
| FrontierMath Tier 4 | — | 2.4% |
| OTIS Mock AIME 2024-2025 | — | 68.1% |

## Knowledge

- DeepSeek-V2.5 (Sep 2024): 34.8 (#193)
- GPT-5.5 Instant: 48.9 (#74)

| Benchmark | DeepSeek-V2.5 (Sep 2024) | GPT-5.5 Instant |
|---|---|---|
| LMArena Expert | 1266 | 1409 |
| GPQA Diamond | — | 82.5% |

## Multimodal

- DeepSeek-V2.5 (Sep 2024): —
- GPT-5.5 Instant: 40.0 (#52)

| Benchmark | DeepSeek-V2.5 (Sep 2024) | GPT-5.5 Instant |
|---|---|---|
| LMArena Vision | — | 1250 |
| LMArena Document | — | 1403 |

## Multilingual

- DeepSeek-V2.5 (Sep 2024): 42.5 (#193)
- GPT-5.5 Instant: 52.8 (#80)

| Benchmark | DeepSeek-V2.5 (Sep 2024) | GPT-5.5 Instant |
|---|---|---|
| LMArena Non-English | 1273 | 1417 |
| LMArena Chinese | 1318 | 1456 |
| LMArena French | 1289 | 1428 |
| LMArena German | 1258 | 1411 |
| LMArena Japanese | 1228 | 1408 |
| LMArena Korean | 1209 | 1392 |
| LMArena Russian | 1289 | 1431 |
| LMArena Spanish | 1248 | 1429 |

## Instruction Following

- DeepSeek-V2.5 (Sep 2024): 67.5 (#194)
- GPT-5.5 Instant: 74.2 (#100)

| Benchmark | DeepSeek-V2.5 (Sep 2024) | GPT-5.5 Instant |
|---|---|---|
| LMArena Instruction Following | 1280 | 1406 |

## Long Context

- DeepSeek-V2.5 (Sep 2024): 39.5 (#174)
- GPT-5.5 Instant: 43.4 (#96)

| Benchmark | DeepSeek-V2.5 (Sep 2024) | GPT-5.5 Instant |
|---|---|---|
| LMArena Longer Query | 1301 | 1422 |

## Writing & Preference

- DeepSeek-V2.5 (Sep 2024): 49.8 (#187)
- GPT-5.5 Instant: 61.8 (#85)

| Benchmark | DeepSeek-V2.5 (Sep 2024) | GPT-5.5 Instant |
|---|---|---|
| LMArena Text | 1294 | 1419 |
| LMArena Creative Writing | 1285 | 1419 |
| LMArena Multi-Turn | 1297 | 1433 |

## FAQ

### Is DeepSeek-V2.5 (Sep 2024) better than GPT-5.5 Instant?

GPT-5.5 Instant is the stronger model overall, scoring 42.7 to 37.6 on the Noometry Index.

### Is DeepSeek-V2.5 (Sep 2024) or GPT-5.5 Instant better for coding?

GPT-5.5 Instant scores higher on coding benchmarks: 44.3 versus 31.7 in the Noometry coding category.

### How many benchmarks do DeepSeek-V2.5 (Sep 2024) and GPT-5.5 Instant share?

17 benchmarks have published results for both models. DeepSeek-V2.5 (Sep 2024) has 22 scored results on Noometry and GPT-5.5 Instant has 27.