Claude Sonnet 5 vs GLM 5.3 Flash
Claude Sonnet 5 
GLM 5.3 Flash Verdict
- Claude Sonnet 5 (high) and GLM 5.3 Flash are level on quality (61.4 vs 61.1).
- Claude Sonnet 5 (high) is stronger in agents & tools, composite.
- GLM 5.3 Flash is stronger in coding, human preference, knowledge, long context, multimodal, reasoning.
- GLM 5.3 Flash is 34× cheaper ($0.119 vs $4.00 per 1M blended).
- GLM 5.3 Flash streams 1.5× faster (90 vs 60 tokens per second).
| Metric | Claude Sonnet 5 (high) | GLM 5.3 Flash |
|---|---|---|
| BenchLeader Index | 61.4 | 61.1 |
| Agents & tools score | 61.8 | 52.1 |
| Coding score | 61.6 | 64.3 |
| Composite score | 69.5 | 61.7 |
| Human preference score | 66.2 | 67.6 |
| Knowledge score | 62.4 | 67.7 |
| Long context score | 64.8 | 66.6 |
| Multimodal score | 63.1 | 65.5 |
| Reasoning score | 66.8 | 67.5 |
| Blended price $/M | $4.00 | $0.119 |
| Output speed | 60 tok/s | 90 tok/s |
| Time to first answer | 10.0 s | 24.9 s |
| Context window | 1M | 1M |
| SciCode | 48.6% | 46.1% |
| WeirdML | 68.8% | – |
| Epoch Capabilities Index | – | 151.4 |
| LMArena Text | 1462 | 1474 |
| LMArena Hard Prompts | 1490 | 1496 |
| LMArena Coding | 1521 | 1534 |
| LMArena WebDev | 1538 | 1605 |
| LMArena Vision | 1278 | 1296 |
| LMArena Agent | 6.3 | 2 |
| LiveBench | – | 71.6% |
| LiveBench Reasoning | – | 77.6% |
| LiveBench Coding | – | 79.0% |
| LiveBench Agentic Coding | – | 56.8% |
| LiveBench Mathematics | – | 81.2% |
| LiveBench Data Analysis | – | 76.4% |
| LiveBench Language | – | 77.3% |
| AA Intelligence Index | 32.0 | 41.9 |
| AA-LCR | 76.7% | 80.0% |
| AA-Omniscience | -3.7 | 7.5 |
| GPQA Diamond (AA) | – | 91.2% |
| Humanity's Last Exam (AA) | 35.7% | 39.9% |
| SciCode (AA) | 54.3% | 51.6% |
Data as of 2026-09-10. Best configuration of each model; every score links to its source on the model pages.
Claude Sonnet 5 vs GLM 5.3 Flash: questions
- Is Claude Sonnet 5 better than GLM 5.3 Flash?
- Claude Sonnet 5 (high) and GLM 5.3 Flash are level on quality (61.4 vs 61.1). The BenchLeader Index combines every independent quality benchmark; Claude Sonnet 5 (high) is ahead overall as of 2026-09-10, but check the category scores for your use.
- Is Claude Sonnet 5 better than GLM 5.3 Flash for coding?
- GLM 5.3 Flash scores higher in coding (64 vs 62 on the category index, where 50 is average).
- Is Claude Sonnet 5 better than GLM 5.3 Flash for agentic tasks?
- Claude Sonnet 5 scores higher in agentic tasks (62 vs 52 on the category index, where 50 is average).
- Which is cheaper, Claude Sonnet 5 or GLM 5.3 Flash?
- GLM 5.3 Flash is cheaper: $0.119 against $4.00 per million tokens, blended at three input tokens per output token.
- Which is faster, Claude Sonnet 5 or GLM 5.3 Flash?
- GLM 5.3 Flash streams faster: 90 against 60 output tokens per second.
- Which has the larger context window?
- Both accept 1M tokens of context.