# Claude Sonnet 5.5 vs DeepSeek-V3

> Claude Sonnet 5.5 is the stronger model overall, scoring 60.5 to 39.2 on the Noometry Index. DeepSeek-V3 costs 9.9× less per token, which makes it the better buy when Claude Sonnet 5.5's lead doesn't matter for your workload.

- Canonical page: https://noometry.com/compare/claude-sonnet-5-5-vs-deepseek-v3
- Last updated: 2026-10-10
- Shared benchmarks: 4

## Summary

- They share 4 benchmarks with published results for both. Claude Sonnet 5.5 scores higher in 4 categories and DeepSeek-V3 in 0 categories; 4 gaps are clear of the uncertainty.
- The widest gap is in math, where Claude Sonnet 5.5 leads 88.7 to 30.4.
- The biggest single-benchmark swing is OTIS Mock AIME 2024-2025: 100% for Claude Sonnet 5.5 and 37.8% for DeepSeek-V3.
- DeepSeek-V3 is cheaper at $0.24 / $0.90 per million input/output tokens, against $2 / $10 for Claude Sonnet 5.5.
- Claude Sonnet 5.5 accepts more context: 1M tokens versus 164K.
- DeepSeek-V3 has downloadable open weights; the other is API-only.

## Snapshot

| | Claude Sonnet 5.5 | DeepSeek-V3 |
|---|---|---|
| Provider | Anthropic | DeepSeek |
| Noometry Index | 60.5 | 39.2 |
| Rank | 10 | 157 |
| Context | 1M | 164K |
| Input $/M | $2 | $0.24 |
| Output $/M | $10 | $0.90 |
| Weights | Proprietary | Open |

## Coding

- Claude Sonnet 5.5: 65.5 (#6)
- DeepSeek-V3: 41.9 (#99)

| Benchmark | Claude Sonnet 5.5 | DeepSeek-V3 |
|---|---|---|
| SciCode | 61% | 35.8% |
| FrontierCode | 52.1% | — |
| Aider Polyglot | — | 55.1% |
| CursorBench | 55.5% | — |
| LMArena WebDev | 1699 | — |
| FrontierSWE | 61.9% | — |
| WeirdML | — | 36.1% |
| BigCodeBench Instruct | — | 50% |
| LiveBench Coding | — | 70.9% |
| LMArena Coding | — | 1368 |
| BigCodeBench Complete | — | 62.2% |
| ALE-Bench | 1,819 | — |
| HumanEval+ | — | 86.6% |
| MBPP+ | — | 73% |

## Agentic & Tool Use

- Claude Sonnet 5.5: 44.9 (#14)
- DeepSeek-V3: —

| Benchmark | Claude Sonnet 5.5 | DeepSeek-V3 |
|---|---|---|
| APEX-Agents | 75.5% | — |
| METR Time Horizons | — | 49.6% |

## Reasoning

- Claude Sonnet 5.5: 52.4 (#29)
- DeepSeek-V3: 20.0 (#226)

| Benchmark | Claude Sonnet 5.5 | DeepSeek-V3 |
|---|---|---|
| CritPt | 31.4% | 0% |
| SimpleBench | — | 27.2% |
| Kagi LLM Benchmark | — | 52.3% |
| LiveBench Reasoning | — | 65.8% |
| LMArena Hard Prompts | — | 1365 |
| Mystery Game Puzzles | 65% | — |
| DTBench | — | 64.8% |
| LiveBench Data Analysis | — | 60.9% |
| LMCA | — | 15.5% |
| BIG-Bench Hard | — | 87.5% |
| Epoch Capabilities Index | — | 135.95 |
| ForecastBench | — | 59.1 |
| HellaSwag | — | 88.9% |
| LiveBench | — | 66.9% |
| PIQA | — | 84.7% |
| WinoGrande | — | 85.2% |

## Math

- Claude Sonnet 5.5: 88.7 (#4)
- DeepSeek-V3: 30.4 (#208)

| Benchmark | Claude Sonnet 5.5 | DeepSeek-V3 |
|---|---|---|
| OTIS Mock AIME 2024-2025 | 100% | 37.8% |
| FrontierMath (Tiers 1-3) | 88.8% | — |
| FrontierMath Tier 4 | 80.5% | — |
| ProofBench | 100% | — |
| Omni-MATH | — | 40.3% |
| LiveBench Math | — | 73.5% |
| LMArena Math | — | 1373 |
| MATH Level 5 | — | 75.5% |
| FrontierMath (Feb 2025 set) | — | 1.7% |

## Knowledge

- Claude Sonnet 5.5: 66.0 (#11)
- DeepSeek-V3: 37.5 (#147)

| Benchmark | Claude Sonnet 5.5 | DeepSeek-V3 |
|---|---|---|
| GPQA Diamond | 95.6% | 67.6% |
| SimpleQA Verified | 46.5% | — |
| MMLU-Pro | — | 72.3% |
| Confabulations | — | 26.1% |
| Vectara Hallucination Rate | — | 6.1% |
| GPQA (HELM) | — | 53.8% |
| LMArena Expert | — | 1352 |
| ARC (AI2) Challenge | — | 95.3% |
| MMLU | — | 87.2% |
| TriviaQA | — | 82.9% |

## Multimodal

- Claude Sonnet 5.5: 53.2 (#5)
- DeepSeek-V3: —

| Benchmark | Claude Sonnet 5.5 | DeepSeek-V3 |
|---|---|---|
| Furniture Assembly | 75% | — |

## Multilingual

- Claude Sonnet 5.5: —
- DeepSeek-V3: 48.8 (#138)

| Benchmark | Claude Sonnet 5.5 | DeepSeek-V3 |
|---|---|---|
| LMArena Non-English | — | 1358 |
| LMArena Chinese | — | 1390 |
| LMArena French | — | 1386 |
| LMArena German | — | 1374 |
| LMArena Japanese | — | 1333 |
| LMArena Korean | — | 1321 |
| LMArena Russian | — | 1372 |
| LMArena Spanish | — | 1358 |

## Instruction Following

- Claude Sonnet 5.5: —
- DeepSeek-V3: 73.0 (#125)

| Benchmark | Claude Sonnet 5.5 | DeepSeek-V3 |
|---|---|---|
| LiveBench Instruction Following | — | 81.5% |
| IFEval | — | 83.2% |
| LMArena Instruction Following | — | 1345 |

## Long Context

- Claude Sonnet 5.5: —
- DeepSeek-V3: 34.0 (#248)

| Benchmark | Claude Sonnet 5.5 | DeepSeek-V3 |
|---|---|---|
| Fiction.LiveBench | — | 50% |
| LMArena Longer Query | — | 1353 |

## Writing & Preference

- Claude Sonnet 5.5: —
- DeepSeek-V3: 57.6 (#124)

| Benchmark | Claude Sonnet 5.5 | DeepSeek-V3 |
|---|---|---|
| LMArena Text | — | 1375 |
| LMArena Creative Writing | — | 1364 |
| Short-Story Creative Writing | — | 77% |
| EQ-Bench Creative Writing | — | 1472 |
| WildBench | — | 83% |
| LMArena Multi-Turn | — | 1389 |
| LiveBench Language | — | 49.1% |

## FAQ

### Is Claude Sonnet 5.5 better than DeepSeek-V3?

Claude Sonnet 5.5 is the stronger model overall, scoring 60.5 to 39.2 on the Noometry Index. DeepSeek-V3 costs 9.9× less per token, which makes it the better buy when Claude Sonnet 5.5's lead doesn't matter for your workload.

### Which is cheaper, Claude Sonnet 5.5 or DeepSeek-V3?

DeepSeek-V3 is cheaper. It lists at $0.24 per million input tokens and $0.90 per million output tokens; Claude Sonnet 5.5 lists at $2 and $10.

### Is Claude Sonnet 5.5 or DeepSeek-V3 better for coding?

Claude Sonnet 5.5 scores higher on coding benchmarks: 65.5 versus 41.9 in the Noometry coding category.

### Which has the bigger context window?

Claude Sonnet 5.5 does, with 1M tokens against 164K.

### How many benchmarks do Claude Sonnet 5.5 and DeepSeek-V3 share?

4 benchmarks have published results for both models. Claude Sonnet 5.5 has 16 scored results on Noometry and DeepSeek-V3 has 60.