GLM 5.3 Flash vs Grok 4.5
GLM 5.3 Flash 
Grok 4.5 Verdict
- Grok 4.5 leads on quality: 63.5 vs 61.1.
- GLM 5.3 Flash is stronger in coding, human preference, long context, multimodal.
- Grok 4.5 is stronger in agents & tools, composite, knowledge, reasoning.
- GLM 5.3 Flash is 25× cheaper ($0.119 vs $3.00 per 1M blended).
- GLM 5.3 Flash streams 1.7× faster (90 vs 52 tokens per second).
| Metric | GLM 5.3 Flash | Grok 4.5 |
|---|---|---|
| BenchLeader Index | 61.1 | 63.5 |
| Agents & tools score | 52.1 | 58.6 |
| Coding score | 64.3 | 59.8 |
| Composite score | 61.7 | 66.2 |
| Human preference score | 67.6 | 67.2 |
| Knowledge score | 67.7 | 76.2 |
| Long context score | 66.6 | 66.2 |
| Multimodal score | 65.5 | 64.9 |
| Reasoning score | 67.5 | 69.2 |
| Blended price $/M | $0.119 | $3.00 |
| Output speed | 90 tok/s | 52 tok/s |
| Time to first answer | 24.9 s | 13.6 s |
| Context window | 1M | 500k |
| SimpleBench | – | 70.0% |
| SciCode | 46.1% | – |
| WeirdML | – | 46.4% |
| APEX-Agents | – | 34.2% |
| FrontierCode | – | 42.4% |
| Epoch Capabilities Index | 151.4 | 153.9 |
| LMArena Text | 1474 | 1471 |
| LMArena Hard Prompts | 1496 | 1495 |
| LMArena Coding | 1534 | 1523 |
| LMArena WebDev | 1605 | 1556 |
| LMArena Vision | 1296 | 1291 |
| LMArena Agent | 2 | 3.9 |
| LiveBench | 71.6% | 75.8% |
| LiveBench Reasoning | 77.6% | 87.2% |
| LiveBench Coding | 79.0% | 68.6% |
| LiveBench Agentic Coding | 56.8% | 56.5% |
| LiveBench Mathematics | 81.2% | 90.8% |
| LiveBench Data Analysis | 76.4% | 73.0% |
| LiveBench Language | 77.3% | 82.8% |
| AA Intelligence Index | 41.9 | 39.1 |
| AA-LCR | 80.0% | 79.3% |
| MMMU-Pro | – | 80.4% |
| AA-Omniscience | 7.5 | 25.3 |
| GPQA Diamond (AA) | 91.2% | 93.1% |
| Humanity's Last Exam (AA) | 39.9% | 42.7% |
| SciCode (AA) | 51.6% | 55.0% |
| Kagi LLM Benchmark | – | 83.5% |
Data as of 2026-09-10. Best configuration of each model; every score links to its source on the model pages.
GLM 5.3 Flash vs Grok 4.5: questions
- Is GLM 5.3 Flash better than Grok 4.5?
- Grok 4.5 leads on quality: 63.5 vs 61.1. The BenchLeader Index combines every independent quality benchmark; Grok 4.5 is ahead overall as of 2026-09-10, but check the category scores for your use.
- Is GLM 5.3 Flash better than Grok 4.5 for coding?
- GLM 5.3 Flash scores higher in coding (64 vs 60 on the category index, where 50 is average).
- Is GLM 5.3 Flash better than Grok 4.5 for agentic tasks?
- Grok 4.5 scores higher in agentic tasks (59 vs 52 on the category index, where 50 is average).
- Which is cheaper, GLM 5.3 Flash or Grok 4.5?
- GLM 5.3 Flash is cheaper: $0.119 against $3.00 per million tokens, blended at three input tokens per output token.
- Which is faster, GLM 5.3 Flash or Grok 4.5?
- GLM 5.3 Flash streams faster: 90 against 52 output tokens per second.
- Which has the larger context window?
- GLM 5.3 Flash accepts more context: 1M against 500k tokens.