Model comparison
Claude Sonnet 4.5 vs Llama 3.1-405B
Claude Sonnet 4.5 is the stronger model overall, scoring 44.1 to 30.7 on the Noometry Index.
Last verified . 33 shared benchmarks.
MetaSummary
- They share 33 benchmarks with published results for both. Claude Sonnet 4.5 scores higher in 9 categories and Llama 3.1-405B in 0 categories; 9 gaps are clear of the uncertainty.
- The widest gap is in writing & preference, where Claude Sonnet 4.5 leads 66.5 to 38.9.
- The biggest single-benchmark swing is OTIS Mock AIME 2024-2025: 77.8% for Claude Sonnet 4.5 and 9.7% for Llama 3.1-405B.
- Llama 3.1-405B has downloadable open weights; the other is API-only.
Side by side
| Claude Sonnet 4.5 | Llama 3.1-405B | |
|---|---|---|
| Provider | Anthropic | Meta |
| Noometry Index | 44.1 | 30.7 |
| Released | 2025-09-29 | 2024-07-23 |
| Weights | Proprietary | Open |
| Context window | 200K | — |
| Max output | 64K | — |
| Input $ / M tokens | $3 | — |
| Output $ / M tokens | $15 | — |
| Results tracked | 73 | 42 |
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Category by category
Coding Claude Sonnet 4.5 leads
Claude Sonnet 4.5: 47.3 (#61), Llama 3.1-405B: 33.1 (#262)
| Benchmark | Claude Sonnet 4.5 | Llama 3.1-405B |
|---|---|---|
| WeirdML | 47.7% | 21.4% |
| LMArena Coding | 1489 | 1291 |
| SWE-bench Verified | 71.3% | — |
| SWE-bench Verified (bash only) | 71.4% | — |
| LMArena WebDev | 1393 | — |
| SWE-bench Multilingual | 67% | — |
| SciCode | 44.7% | — |
| GSO | 14.7% | — |
| ALE-Bench | 796.15 | — |
| AlgoTune | 1.52 | — |
Agentic & Tool Use Claude Sonnet 4.5 leads
Claude Sonnet 4.5: 38.3 (#32), Llama 3.1-405B: 21.0 (#140)
| Benchmark | Claude Sonnet 4.5 | Llama 3.1-405B |
|---|---|---|
| Cybench | 60% | 7.5% |
| Terminal-Bench | 46.5% | — |
| Berkeley Function Calling Leaderboard | 73.2% | — |
| GDPval | 42.5% | — |
| Remote Labor Index | 2.1% | — |
| TheAgentCompany | — | 7.4% |
| τ²-bench Airline | 72% | — |
| τ²-bench Banking | 25.3% | — |
| τ²-bench Retail | 72.4% | — |
| τ²-bench Telecom | 84.9% | — |
| DeepResearch Bench | 52.6% | — |
| OSWorld | 62.9% | — |
| LMArena Search | 1159 | — |
| METR Time Horizons | 67.4% | — |
| Vending-Bench 2 | 3,839 | — |
Reasoning Claude Sonnet 4.5 leads
Claude Sonnet 4.5: 26.9 (#125), Llama 3.1-405B: 16.8 (#300)
| Benchmark | Claude Sonnet 4.5 | Llama 3.1-405B |
|---|---|---|
| SimpleBench | 54.3% | 23% |
| Kagi LLM Benchmark | 57.9% | 45% |
| LMArena Hard Prompts | 1462 | 1269 |
| DTBench | 83.2% | 61.4% |
| Epoch Capabilities Index | 146.84 | 128.75 |
| ForecastBench | 61.9 | 59.9 |
| ARC-AGI-2 | 13.6% | — |
| NYT Connections (extended) | 37.3% | — |
| ARC-AGI-1 | 63.7% | — |
| CritPt | 1.1% | — |
| Chess Puzzles | 12% | — |
| EnigmaEval | 6% | — |
| EBR-Bench | 2.4% | — |
| Mystery Game Puzzles | 17% | — |
| LMCA | 38.8% | — |
| BIG-Bench Hard | — | 82.9% |
| HellaSwag | — | 89.2% |
| PIQA | — | 85.9% |
| WinoGrande | — | 89.2% |
Math Claude Sonnet 4.5 leads
Claude Sonnet 4.5: 32.3 (#216), Llama 3.1-405B: 18.4 (#290)
| Benchmark | Claude Sonnet 4.5 | Llama 3.1-405B |
|---|---|---|
| OTIS Mock AIME 2024-2025 | 77.8% | 9.7% |
| Omni-MATH | 55.3% | 24.9% |
| LMArena Math | 1449 | 1281 |
| MATH Level 5 | 97.7% | 49.8% |
| FrontierMath (Tiers 1-3) | 23.9% | — |
| FrontierMath Tier 4 | 2.4% | — |
| ProofBench | 19% | — |
| FrontierMath (Feb 2025 set) | 15.2% | — |
| FrontierMath Tier 4 (v1) | 4.2% | — |
Knowledge Claude Sonnet 4.5 leads
Claude Sonnet 4.5: 48.4 (#76), Llama 3.1-405B: 30.4 (#227)
| Benchmark | Claude Sonnet 4.5 | Llama 3.1-405B |
|---|---|---|
| GPQA Diamond | 82.3% | 50.9% |
| MMLU-Pro | 86.9% | 72.3% |
| GPQA (HELM) | 68.6% | 52.2% |
| LMArena Expert | 1482 | 1243 |
| Humanity's Last Exam | 13.7% | — |
| SimpleQA Verified | 30.7% | — |
| Confabulations | — | 17.6% |
| Vectara Hallucination Rate | 12% | — |
| ARC (AI2) Challenge | — | 95.3% |
| MMLU | — | 84.5% |
| TriviaQA | — | 82.7% |
Multimodal Not comparable
Claude Sonnet 4.5: 34.8 (#89), Llama 3.1-405B: —
| Benchmark | Claude Sonnet 4.5 | Llama 3.1-405B |
|---|---|---|
| VPCT | 39.8% | — |
| LMArena Document | 1450 | — |
Multilingual Claude Sonnet 4.5 leads
Claude Sonnet 4.5: 53.4 (#69), Llama 3.1-405B: 40.7 (#214)
| Benchmark | Claude Sonnet 4.5 | Llama 3.1-405B |
|---|---|---|
| LMArena Non-English | 1425 | 1248 |
| LMArena Chinese | 1459 | 1242 |
| LMArena French | 1458 | 1279 |
| LMArena German | 1427 | 1252 |
| LMArena Japanese | 1390 | 1208 |
| LMArena Korean | 1403 | 1184 |
| LMArena Russian | 1437 | 1265 |
| LMArena Spanish | 1457 | 1260 |
Instruction Following Claude Sonnet 4.5 leads
Claude Sonnet 4.5: 75.0 (#78), Llama 3.1-405B: 65.9 (#214)
| Benchmark | Claude Sonnet 4.5 | Llama 3.1-405B |
|---|---|---|
| IFEval | 85% | 81.1% |
| LMArena Instruction Following | 1459 | 1259 |
Long Context Claude Sonnet 4.5 leads
Claude Sonnet 4.5: 45.2 (#46), Llama 3.1-405B: 38.4 (#197)
| Benchmark | Claude Sonnet 4.5 | Llama 3.1-405B |
|---|---|---|
| LMArena Longer Query | 1476 | 1266 |
Writing & Preference Claude Sonnet 4.5 leads
Claude Sonnet 4.5: 66.5 (#34), Llama 3.1-405B: 38.9 (#251)
| Benchmark | Claude Sonnet 4.5 | Llama 3.1-405B |
|---|---|---|
| LMArena Text | 1439 | 1284 |
| LMArena Creative Writing | 1442 | 1262 |
| EQ-Bench Creative Writing | 1678 | 870 |
| WildBench | 85.4% | 78.3% |
| LMArena Multi-Turn | 1465 | 1297 |
Frequently asked questions
Is Claude Sonnet 4.5 better than Llama 3.1-405B?
Claude Sonnet 4.5 is the stronger model overall, scoring 44.1 to 30.7 on the Noometry Index.
Is Claude Sonnet 4.5 or Llama 3.1-405B better for coding?
Claude Sonnet 4.5 scores higher on coding benchmarks: 47.3 versus 33.1 in the Noometry coding category.
How many benchmarks do Claude Sonnet 4.5 and Llama 3.1-405B share?
33 benchmarks have published results for both models. Claude Sonnet 4.5 has 73 scored results on Noometry and Llama 3.1-405B has 42.