GLM 5.1 vs Grok 4.1 Fast
Head to head on 23 shared benchmarks, with price, context window, and release dates.
Benchmark scores
44evals · sort by any column, ⤢ to expand fullscreen
| Model | |||||||||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| GLM 5.1 Zai | 64.5% | 1589elo | 73.5 | 83.9% | 27.9% | 52.0% | 72.7% | 75.4% | 63.2% | 68.5% | 71.8% | 84.9% | 72.5% | 67.0% | 41.6% | 72.3% | 85.4% | 22.2% | 36.1% | 71.2% | 35.6% | 31.5% | 97.1% | - | - | 20.8% | 35.9% | 1.13 | 40.0% | 44.8% | 33.5% | 34.7% | 15.1% | - | - | - | - | - | - | - | 34.6% | 5.24 | 69.8 | 52.5% | 53.6% |
| Grok 4.1 Fast xAI | 66.0% | 1324elo | 40.1 | 63.7% | 5.1% | 36.5% | 64.7% | 69.6% | 52.2% | 28.2% | 74.3% | 83.7% | 80.2% | 60.8% | 28.1% | 78.7% | 74.3% | 4.0% | 29.6% | 73.1% | 14.4% | 1.2% | 63.7% | 62.0% | 34.3% | - | - | - | - | - | - | - | - | 11.8 | 35.0% | 80.2% | 39.9% | 100.0% | 42.6% | 31.3% | - | - | - | - | 51.0% |
2 / 2 models
| Attribute | GLM 5.1 Zai | Grok 4.1 Fast xAI |
|---|---|---|
| Description | GLM-5.1 is an AI model from Zai, released with open weights. | Grok 4.1 Fast is an AI model from xAI. |
| Family | Glm | Grok |
| Params | - | - |
| Open weights | open | closed |
| License | mit | proprietary |
| Released | 7 Apr 2026 | 19 Nov 2025 |
| Context | 204,800 | - |
| Input $/1M | $1.39 | - |
| Output $/1M | $4.40 | - |
| Cache read $/1M | $0.234 | - |
| Cache write $/1M | - | - |
| Speed | 0 tok/s | 0 tok/s |
| Latency | 0.00 s | 0.00 s |
| Modalities | text | text |
| Providers | - | - |
| Publisher | Zai | xAI |
| Reported scores | IFBench52.0% (AA) τ²-bench (Tau²-bench)97.1% (AA) Terminal-Bench (Hard)35.6% (AA) Vals Index52.5% Vibe Code Bench v1.131.5% | Infraresolutionbench80.2% (150 samples) Agent Diff Bench62.0% (179 samples) Medpt100.0% (15 samples) Hanabi11.8 (15 samples) SciCode29.6% (AA) |
FAQ
- Is GLM 5.1 or Grok 4.1 Fast better?
- Across the 23 benchmarks both models report on Sophon, GLM 5.1 leads on 18 of them. Which one is "better" depends on the benchmark - the table above shows every shared score.
- How do GLM 5.1 and Grok 4.1 Fast compare on GPQA Diamond?
- GLM 5.1 scores 83.9% and Grok 4.1 Fast scores 63.7% on GPQA Diamond.
- When were GLM 5.1 and Grok 4.1 Fast released?
- GLM 5.1 was released 7 Apr 2026 by Zai. Grok 4.1 Fast was released 19 Nov 2025 by xAI.
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