Comparing 2 models
Claude Sonnet 5.5 vs Gemini 3.5 Flash
Benchmarks through
Verdict
Claude Sonnet 5.5 and Gemini 3.5 Flash are not yet ranked on the same task, so compare the specifications below. Gemini 3.5 Flash costs 1.3x less per input token. Gemini 3.5 Flash accepts 1.0x more context.
Built from the published task rankings below; ranks come from each task's own weighted benchmarks, so a win on one task says nothing about another.
Measured head to head
Benchmarks both models were run on
| Evaluation | Claude Sonnet 5.5 | Gemini 3.5 Flash | Source |
|---|---|---|---|
| Design Arena Coding | 1366 Elo | 1268 Elo | source · 2026-10-16 |
| Design Arena UI | 1378 Elo | 1272 Elo | source · 2026-10-16 |
| Design Arena Website | 1330 Elo | 1269 Elo | source · 2026-10-16 |
| FrontierMath Tiers 1-3 (Epoch AI) | 88.8% ± 1.9 | 62.8% ± 2.9 | source · 2026-09-29 |
| GPQA Diamond (Epoch AI) | 95.6% ± 1.4 | 92.8% ± 1.6 | source · 2026-09-29 |
| LiveBench Agentic Coding | 56.3% | 49.0% | source · 2026-10-16 |
| LiveBench Coding | 91.4% | 78.2% | source · 2026-10-16 |
| LiveBench Data Analysis | 59.5% | 64.9% | source · 2026-10-16 |
| LiveBench Instruction Following | 56.8% | 75.6% | source · 2026-10-16 |
| LiveBench Language | 78.0% | 84.6% | source · 2026-10-16 |
| LiveBench Math | 96.1% | 88.2% | source · 2026-10-16 |
| LiveBench Reasoning | 91.6% | 82% | source · 2026-10-16 |
| LMArena Creative Writing | 1467 Elo | 1468 Elo | source · 2026-10-15 |
| LMArena Instruction Following | 1488 Elo | 1467 Elo | source · 2026-10-15 |
| LMArena Long Query | 1494 Elo | 1483 Elo | source · 2026-10-15 |
| LMArena Math | 1499 Elo | 1503 Elo | source · 2026-10-15 |
| LMArena Text | 1475 Elo | 1477 Elo | source · 2026-10-15 |
| LMArena Text Factuality | 1474 Elo | 1477 Elo | source · 2026-10-15 |
| LMArena Vision | 1266 Elo | 1284 Elo | source · 2026-10-09 |
| LMArena Vision Diagrams | 1320 Elo | 1309 Elo | source · 2026-10-09 |
| LMArena Vision OCR | 1280 Elo | 1293 Elo | source · 2026-10-09 |
| LMArena WebDev | 1774 Elo | 1499 Elo | source · 2026-10-13 |
| LMArena WebDev Image-to-Web | 1740 Elo | 1501 Elo | source · 2026-10-09 |
| OTIS Mock AIME (Epoch AI) | 100% ± 0 | 95.6% ± 2.7 | source · 2026-09-29 |
| SimpleQA Verified (Epoch AI) | 46.5% ± 1.6 | 66.2% ± 1.5 | source · 2026-09-29 |
Values are as published by each evaluator, in its own units; rows from different evaluators are not on a common scale.
task evidence
How they place when the question changes
Lower ranks are better. “Best” marks the strongest option in this shortlist for that task.