# DeepSeek V4.1 Flash vs GPT-5.3 Chat

> DeepSeek V4.1 Flash is the stronger model overall, scoring 50.3 to 42.1 on the Noometry Index.

- Canonical page: https://noometry.com/compare/deepseek-v4-1-flash-vs-gpt-5-3-chat
- Last updated: 2026-10-10
- Shared benchmarks: 15

## Summary

- They share 15 benchmarks with published results for both. DeepSeek V4.1 Flash scores higher in 8 categories and GPT-5.3 Chat in 0 categories; 8 gaps are clear of the uncertainty.
- The widest gap is in reasoning, where DeepSeek V4.1 Flash leads 46.2 to 27.3.
- DeepSeek V4.1 Flash is cheaper at $0.15 / $0.60 per million input/output tokens, against $1.75 / $14 for GPT-5.3 Chat.
- DeepSeek V4.1 Flash accepts more context: 1M tokens versus 128K.
- DeepSeek V4.1 Flash has downloadable open weights; the other is API-only.

## Snapshot

| | DeepSeek V4.1 Flash | GPT-5.3 Chat |
|---|---|---|
| Provider | DeepSeek | OpenAI |
| Noometry Index | 50.3 | 42.1 |
| Rank | 40 | 109 |
| Context | 1M | 128K |
| Input $/M | $0.15 | $1.75 |
| Output $/M | $0.60 | $14 |
| Weights | Open | Proprietary |

## Coding

- DeepSeek V4.1 Flash: 52.8 (#29)
- GPT-5.3 Chat: 40.8 (#124)

| Benchmark | DeepSeek V4.1 Flash | GPT-5.3 Chat |
|---|---|---|
| LMArena Coding | 1511 | 1408 |
| LMArena WebDev | 1620 | — |
| SciCode | 51.9% | — |
| ALE-Bench | 1,092 | — |

## Reasoning

- DeepSeek V4.1 Flash: 46.2 (#39)
- GPT-5.3 Chat: 27.3 (#105)

| Benchmark | DeepSeek V4.1 Flash | GPT-5.3 Chat |
|---|---|---|
| LMArena Hard Prompts | 1485 | 1399 |
| NYT Connections (extended) | 89.6% | — |
| CritPt | 14.3% | — |
| DTBench | 89.9% | — |
| LMCA | 47% | — |
| Surface Evolver Bench | 46.3% | — |
| Epoch Capabilities Index | 155.01 | — |

## Math

- DeepSeek V4.1 Flash: 48.4 (#52)
- GPT-5.3 Chat: 35.4 (#146)

| Benchmark | DeepSeek V4.1 Flash | GPT-5.3 Chat |
|---|---|---|
| LMArena Math | 1493 | 1389 |
| ProofBench | 54% | — |

## Knowledge

- DeepSeek V4.1 Flash: 41.6 (#97)
- GPT-5.3 Chat: 38.2 (#137)

| Benchmark | DeepSeek V4.1 Flash | GPT-5.3 Chat |
|---|---|---|
| LMArena Expert | 1505 | 1397 |

## Multilingual

- DeepSeek V4.1 Flash: 55.5 (#29)
- GPT-5.3 Chat: 50.5 (#119)

| Benchmark | DeepSeek V4.1 Flash | GPT-5.3 Chat |
|---|---|---|
| LMArena Non-English | 1452 | 1383 |
| LMArena Chinese | 1506 | 1433 |
| LMArena French | 1448 | 1398 |
| LMArena Russian | 1473 | 1400 |
| LMArena Spanish | 1499 | 1371 |
| LMArena German | — | 1384 |
| LMArena Japanese | — | 1351 |
| LMArena Korean | — | 1347 |

## Instruction Following

- DeepSeek V4.1 Flash: 77.6 (#24)
- GPT-5.3 Chat: 73.0 (#124)

| Benchmark | DeepSeek V4.1 Flash | GPT-5.3 Chat |
|---|---|---|
| LMArena Instruction Following | 1475 | 1378 |

## Long Context

- DeepSeek V4.1 Flash: 45.2 (#46)
- GPT-5.3 Chat: 42.6 (#115)

| Benchmark | DeepSeek V4.1 Flash | GPT-5.3 Chat |
|---|---|---|
| LMArena Longer Query | 1476 | 1396 |

## Writing & Preference

- DeepSeek V4.1 Flash: 65.8 (#43)
- GPT-5.3 Chat: 63.3 (#65)

| Benchmark | DeepSeek V4.1 Flash | GPT-5.3 Chat |
|---|---|---|
| LMArena Text | 1465 | 1389 |
| LMArena Creative Writing | 1436 | 1356 |
| EQ-Bench Creative Writing | 1540 | 1690 |
| LMArena Multi-Turn | 1460 | 1413 |

## FAQ

### Is DeepSeek V4.1 Flash better than GPT-5.3 Chat?

DeepSeek V4.1 Flash is the stronger model overall, scoring 50.3 to 42.1 on the Noometry Index.

### Which is cheaper, DeepSeek V4.1 Flash or GPT-5.3 Chat?

DeepSeek V4.1 Flash is cheaper. It lists at $0.15 per million input tokens and $0.60 per million output tokens; GPT-5.3 Chat lists at $1.75 and $14.

### Is DeepSeek V4.1 Flash or GPT-5.3 Chat better for coding?

DeepSeek V4.1 Flash scores higher on coding benchmarks: 52.8 versus 40.8 in the Noometry coding category.

### Which has the bigger context window?

DeepSeek V4.1 Flash does, with 1M tokens against 128K.

### How many benchmarks do DeepSeek V4.1 Flash and GPT-5.3 Chat share?

15 benchmarks have published results for both models. DeepSeek V4.1 Flash has 25 scored results on Noometry and GPT-5.3 Chat has 18.