Comparing 2 models
Claude Sonnet 5.5 vs GLM 5.3 Flash
Benchmarks through
Verdict
Claude Sonnet 5.5 places higher on 6 of the 7 tasks where both are ranked. GLM 5.3 Flash costs 82.3x less per input token. GLM 5.3 Flash accepts 1.0x more context. Only GLM 5.3 Flash has open weights for self-hosting.
- Choose Claude Sonnet 5.5 for Code Completion (#1), OpenClaw (#3), Goose (#3).
- Choose GLM 5.3 Flash for Vision & Documents (#7), you need to self-host.
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 | GLM 5.3 Flash | Source |
|---|---|---|---|
| Design Arena Coding | 1366 Elo | 1285 Elo | source · 2026-10-16 |
| Design Arena UI | 1378 Elo | 1318 Elo | source · 2026-10-16 |
| Design Arena Website | 1330 Elo | 1274 Elo | source · 2026-10-16 |
| FrontierMath Tiers 1-3 (Epoch AI) | 88.8% ± 1.9 | 55.8% ± 2.9 | source · 2026-09-29 |
| GPQA Diamond (Epoch AI) | 95.6% ± 1.4 | 90.2% ± 1.7 | source · 2026-09-29 |
| LiveBench Agentic Coding | 56.3% | 56.8% | source · 2026-10-16 |
| LiveBench Coding | 91.4% | 79.0% | source · 2026-10-16 |
| LiveBench Data Analysis | 59.5% | 76.4% | source · 2026-10-16 |
| LiveBench Instruction Following | 56.8% | 52.8% | source · 2026-10-16 |
| LiveBench Language | 78.0% | 77.3% | source · 2026-10-16 |
| LiveBench Math | 96.1% | 81.2% | source · 2026-10-16 |
| LiveBench Reasoning | 91.6% | 77.6% | source · 2026-10-16 |
| LMArena Agent | 12.5 | -1.1 | source · 2026-10-14 |
| LMArena Agent Bash Recovery | 15 | -5.7 | source · 2026-10-08 |
| LMArena Agent Steerability | 12.3 | -3 | source · 2026-10-14 |
| LMArena Agent Task Outcome | 20 | 3.9 | source · 2026-10-14 |
| LMArena Agent Tool Hallucination | 0.5 | 0.6 | source · 2026-10-14 |
| LMArena Creative Writing | 1467 Elo | 1441 Elo | source · 2026-10-15 |
| LMArena Instruction Following | 1488 Elo | 1478 Elo | source · 2026-10-15 |
| LMArena Long Query | 1494 Elo | 1482 Elo | source · 2026-10-15 |
| LMArena Math | 1499 Elo | 1505 Elo | source · 2026-10-15 |
| LMArena Text | 1475 Elo | 1474 Elo | source · 2026-10-15 |
| LMArena Text Factuality | 1474 Elo | 1463 Elo | source · 2026-10-15 |
| LMArena Vision | 1266 Elo | 1273 Elo | source · 2026-10-09 |
| LMArena Vision Diagrams | 1320 Elo | 1306 Elo | source · 2026-10-09 |
| LMArena Vision OCR | 1280 Elo | 1284 Elo | source · 2026-10-09 |
| LMArena WebDev | 1774 Elo | 1606 Elo | source · 2026-10-13 |
| LMArena WebDev Image-to-Web | 1740 Elo | 1581 Elo | source · 2026-10-09 |
| OTIS Mock AIME (Epoch AI) | 100% ± 0 | 93.9% ± 2.2 | source · 2026-09-29 |
| Terminal-Bench (4.0) | 61.8% | 35.8% | source · 2026-10-16 |
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.