Claude Opus 4.8 vs GLM 5.3 Flash
Claude Opus 4.8 
GLM 5.3 Flash Verdict
- Claude Opus 4.8 leads on quality: 64.8 vs 61.1.
- Claude Opus 4.8 is stronger in agents & tools, coding, composite, instruction following.
- GLM 5.3 Flash is stronger in human preference, knowledge, long context, multimodal, reasoning.
- GLM 5.3 Flash is 84× cheaper ($0.119 vs $10.00 per 1M blended).
- GLM 5.3 Flash streams 1.6× faster (90 vs 56 tokens per second).
| Metric | Claude Opus 4.8 | GLM 5.3 Flash |
|---|---|---|
| BenchLeader Index | 64.8 | 61.1 |
| Agents & tools score | 65.0 | 52.1 |
| Coding score | 65.6 | 64.3 |
| Composite score | 82.1 | 61.7 |
| Human preference score | 65.8 | 67.6 |
| Instruction following score | 61.8 | – |
| Knowledge score | 66.5 | 67.7 |
| Long context score | 65.4 | 66.6 |
| Multimodal score | 64.5 | 65.5 |
| Reasoning score | 64.6 | 67.5 |
| Blended price $/M | $10.00 | $0.119 |
| Output speed | 56 tok/s | 90 tok/s |
| Time to first answer | 29.3 s | 24.9 s |
| Context window | 1M | 1M |
| SimpleBench | 64.8% | – |
| SciCode | – | 46.1% |
| Remote Labor Index | 8.3% | – |
| FrontierCode | 46.5% | – |
| GSO-Bench | 47.1% | – |
| Epoch Capabilities Index | 158.3 | 151.4 |
| LMArena Text | 1473 | 1474 |
| LMArena Hard Prompts | 1503 | 1496 |
| LMArena Coding | 1527 | 1534 |
| LMArena WebDev | 1540 | 1605 |
| LMArena Vision | 1289 | 1296 |
| LMArena Agent | – | 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 | 42.0 | 41.9 |
| IFBench | 62.2% | – |
| AA-LCR | 77.7% | 80.0% |
| AA-Omniscience | 28.8 | 7.5 |
| Terminal-Bench Hard | 58.3% | – |
| GPQA Diamond (AA) | 92.0% | 91.2% |
| Humanity's Last Exam (AA) | 48.7% | 39.9% |
| SciCode (AA) | 54.4% | 51.6% |
| τ²-Bench Telecom (AA) | 94.4% | – |
| LiveCodeBench | 87.8% | – |
| MMLU-Pro | 89.6% | – |
| LegalBench | 83.6% | – |
| CorpFin | 66.7% | – |
| TaxEval | 75.6% | – |
| Terminal-Bench 2.1 (Vals) | 71.9% | – |
| SWE-bench (Vals) | 88.6% | – |
| GPQA Diamond (Vals) | 92.4% | – |
| Vals Index | 60.9 | – |
| HiL-Bench | 35.3% | – |
| EQ-Bench 4 | 1281 | – |
Data as of 2026-09-10. Best configuration of each model; every score links to its source on the model pages.
Claude Opus 4.8 vs GLM 5.3 Flash: questions
- Is Claude Opus 4.8 better than GLM 5.3 Flash?
- Claude Opus 4.8 leads on quality: 64.8 vs 61.1. The BenchLeader Index combines every independent quality benchmark; Claude Opus 4.8 is ahead overall as of 2026-09-10, but check the category scores for your use.
- Is Claude Opus 4.8 better than GLM 5.3 Flash for coding?
- Claude Opus 4.8 scores higher in coding (66 vs 64 on the category index, where 50 is average).
- Is Claude Opus 4.8 better than GLM 5.3 Flash for agentic tasks?
- Claude Opus 4.8 scores higher in agentic tasks (65 vs 52 on the category index, where 50 is average).
- Which is cheaper, Claude Opus 4.8 or GLM 5.3 Flash?
- GLM 5.3 Flash is cheaper: $0.119 against $10.00 per million tokens, blended at three input tokens per output token.
- Which is faster, Claude Opus 4.8 or GLM 5.3 Flash?
- GLM 5.3 Flash streams faster: 90 against 56 output tokens per second.
- Which has the larger context window?
- Both accept 1M tokens of context.