# DeepSeek-V3.1 vs GPT-5.3 Chat

> DeepSeek-V3.1 and GPT-5.3 Chat score almost the same on the Noometry Index (42.2 vs 42.1), so choose on price, context window or the category you care about most.

- Canonical page: https://noometry.com/compare/deepseek-v3-1-vs-gpt-5-3-chat
- Last updated: 2026-10-10
- Shared benchmarks: 18

## Summary

- They share 18 benchmarks with published results for both. DeepSeek-V3.1 scores higher in 4 categories and GPT-5.3 Chat in 4 categories; 5 gaps are clear of the uncertainty.
- The widest gap is in long context, where GPT-5.3 Chat leads 42.6 to 36.3.
- DeepSeek-V3.1 is cheaper at $0.25 / $0.95 per million input/output tokens, against $1.75 / $14 for GPT-5.3 Chat.
- DeepSeek-V3.1 accepts more context: 164K tokens versus 128K.
- DeepSeek-V3.1 has downloadable open weights; the other is API-only.

## Snapshot

| | DeepSeek-V3.1 | GPT-5.3 Chat |
|---|---|---|
| Provider | DeepSeek | OpenAI |
| Noometry Index | 42.2 | 42.1 |
| Rank | 106 | 109 |
| Context | 164K | 128K |
| Input $/M | $0.25 | $1.75 |
| Output $/M | $0.95 | $14 |
| Weights | Open | Proprietary |

## Coding

- DeepSeek-V3.1: 39.8 (#140)
- GPT-5.3 Chat: 40.8 (#124)

| Benchmark | DeepSeek-V3.1 | GPT-5.3 Chat |
|---|---|---|
| LMArena Coding | 1417 | 1408 |
| WeirdML | 38.4% | — |

## Reasoning

- DeepSeek-V3.1: 27.3 (#109)
- GPT-5.3 Chat: 27.3 (#105)

| Benchmark | DeepSeek-V3.1 | GPT-5.3 Chat |
|---|---|---|
| LMArena Hard Prompts | 1417 | 1399 |
| SimpleBench | 40% | — |
| Kagi LLM Benchmark | 53.2% | — |
| DTBench | 82.7% | — |
| LMCA | 24.3% | — |
| Epoch Capabilities Index | 139.92 | — |
| ForecastBench | 58 | — |

## Math

- DeepSeek-V3.1: 36.1 (#125)
- GPT-5.3 Chat: 35.4 (#146)

| Benchmark | DeepSeek-V3.1 | GPT-5.3 Chat |
|---|---|---|
| LMArena Math | 1420 | 1389 |

## Knowledge

- DeepSeek-V3.1: 43.0 (#86)
- GPT-5.3 Chat: 38.2 (#137)

| Benchmark | DeepSeek-V3.1 | GPT-5.3 Chat |
|---|---|---|
| LMArena Expert | 1403 | 1397 |
| Vectara Hallucination Rate | 5.5% | — |

## Multilingual

- DeepSeek-V3.1: 51.8 (#100)
- GPT-5.3 Chat: 50.5 (#119)

| Benchmark | DeepSeek-V3.1 | GPT-5.3 Chat |
|---|---|---|
| LMArena Non-English | 1400 | 1383 |
| LMArena Chinese | 1470 | 1433 |
| LMArena French | 1447 | 1398 |
| LMArena German | 1412 | 1384 |
| LMArena Japanese | 1374 | 1351 |
| LMArena Korean | 1337 | 1347 |
| LMArena Russian | 1405 | 1400 |
| LMArena Spanish | 1429 | 1371 |

## Instruction Following

- DeepSeek-V3.1: 74.1 (#105)
- GPT-5.3 Chat: 73.0 (#124)

| Benchmark | DeepSeek-V3.1 | GPT-5.3 Chat |
|---|---|---|
| LMArena Instruction Following | 1400 | 1378 |

## Long Context

- DeepSeek-V3.1: 36.3 (#227)
- GPT-5.3 Chat: 42.6 (#115)

| Benchmark | DeepSeek-V3.1 | GPT-5.3 Chat |
|---|---|---|
| LMArena Longer Query | 1422 | 1396 |
| Fiction.LiveBench | 52.8% | — |

## Writing & Preference

- DeepSeek-V3.1: 60.5 (#93)
- GPT-5.3 Chat: 63.3 (#65)

| Benchmark | DeepSeek-V3.1 | GPT-5.3 Chat |
|---|---|---|
| LMArena Text | 1420 | 1389 |
| LMArena Creative Writing | 1401 | 1356 |
| EQ-Bench Creative Writing | 1436 | 1690 |
| LMArena Multi-Turn | 1408 | 1413 |

## FAQ

### Is DeepSeek-V3.1 better than GPT-5.3 Chat?

DeepSeek-V3.1 and GPT-5.3 Chat score almost the same on the Noometry Index (42.2 vs 42.1), so choose on price, context window or the category you care about most.

### Which is cheaper, DeepSeek-V3.1 or GPT-5.3 Chat?

DeepSeek-V3.1 is cheaper. It lists at $0.25 per million input tokens and $0.95 per million output tokens; GPT-5.3 Chat lists at $1.75 and $14.

### Is DeepSeek-V3.1 or GPT-5.3 Chat better for coding?

They score almost the same on coding (39.8 vs 40.8); test both on your own repository before choosing.

### Which has the bigger context window?

DeepSeek-V3.1 does, with 164K tokens against 128K.

### How many benchmarks do DeepSeek-V3.1 and GPT-5.3 Chat share?

18 benchmarks have published results for both models. DeepSeek-V3.1 has 27 scored results on Noometry and GPT-5.3 Chat has 18.