Z.ai · released Aug 14, 2026
GLM-5.3
GLM-5.3 is Z.ai's open-weight model and handles chat decently at a low price.
Open weights3 months oldThinks before answering
- Input price
- $1.2 / M
- Output price
- $4.18 / M
- Context
- 1M tokens
- Longest reply
- 131K
- Reads
- text
- Knows up to
- –
Where it shines
- Its weights are open to download.
- It scores 1496 on hard English prompts.
- It costs about $1.20 in, $4.18 out.
Where it struggles
- Its research job score of 40 is weak.
Where you can use it
- Hugging FaceDownloadWeights are public.
- Z.ai APIAPIAbout $1.20 in / $4.18 out per million tokens.
- OpenRouterAPIListed as
z-ai/glm-5.3
How it scores on each job
Scores run 0 to 100 and blend every measure we have for that job. The number after the dot is its rank among the 33 models in the lineup.
The evidence
| Measure | Score | Rank in lineup | Source |
|---|---|---|---|
| Epoch Capabilities Index | 156 | #18 | Epoch AI |
| LMArena text | 1474 | #12 | LMArena |
| LMArena hard prompts | 1490 | #13 | LMArena |
| LMArena instruction following | 1480 | #11 | LMArena |
| LMArena multi-turn | 1470 | #14 | LMArena |
| LMArena creative writing | 1459 | #12 | LMArena |
| LMArena writing & language | 1469 | #13 | LMArena |
| LMArena coding | 1498 | #14 | LMArena |
| LMArena math | 1498 | #11 | LMArena |
| LMArena business & finance | 1459 | #16 | LMArena |
| LMArena legal & government | 1473 | #16 | LMArena |
| LMArena medicine | 1482 | #13 | LMArena |
| WebDev Arena | 1623 | #15 | LMArena |
| Agent Arena | #23 | #13 | LMArena |
| GPQA Diamond | 91% | #17 | Epoch AI |
| FrontierMath | 69% | #18 | Epoch AI |
| SimpleQA Verified | 41% | #20 | Epoch AI |
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