# GLM-5.1 vs Grok 4.20 (Non-Reasoning)

> GLM-5.1 and Grok 4.20 (Non-Reasoning) score almost the same on the Noometry Index (47.6 vs 48.5), so choose on price, context window or the category you care about most.

- Canonical page: https://noometry.com/compare/glm-5-1-vs-grok-4-20
- Last updated: 2026-10-10
- Shared benchmarks: 31

## Summary

- They share 31 benchmarks with published results for both. GLM-5.1 scores higher in 6 categories and Grok 4.20 (Non-Reasoning) in 3 categories; 6 gaps are clear of the uncertainty.
- The widest gap is in reasoning, where Grok 4.20 (Non-Reasoning) leads 52.2 to 38.2.
- The biggest single-benchmark swing is ProofBench: 22.2% for GLM-5.1 and 14% for Grok 4.20 (Non-Reasoning).
- Grok 4.20 (Non-Reasoning) is cheaper at $1.25 / $2.50 per million input/output tokens, against $1.40 / $4.40 for GLM-5.1.
- Grok 4.20 (Non-Reasoning) accepts more context: 1M tokens versus 200K.
- GLM-5.1 has downloadable open weights; the other is API-only.

## Snapshot

| | GLM-5.1 | Grok 4.20 (Non-Reasoning) |
|---|---|---|
| Provider | Z.ai (Zhipu) | xAI |
| Noometry Index | 47.6 | 48.5 |
| Rank | 51 | 48 |
| Context | 200K | 1M |
| Input $/M | $1.40 | $1.25 |
| Output $/M | $4.40 | $2.50 |
| Weights | Open | Proprietary |

## Coding

- GLM-5.1: 48.5 (#52)
- Grok 4.20 (Non-Reasoning): 41.8 (#104)

| Benchmark | GLM-5.1 | Grok 4.20 (Non-Reasoning) |
|---|---|---|
| LMArena WebDev | 1509 | 1374 |
| WeirdML | 57.1% | 52.3% |
| LMArena Coding | 1486 | 1458 |
| ALE-Bench | 887.1 | 1,150 |
| SWE-bench Verified | 74.2% | — |
| SciCode | 43.8% | — |

## Agentic & Tool Use

- GLM-5.1: 24.8 (#106)
- Grok 4.20 (Non-Reasoning): 34.3 (#43)

| Benchmark | GLM-5.1 | Grok 4.20 (Non-Reasoning) |
|---|---|---|
| Vending-Bench 2 | 5,634 | 4,663 |
| Terminal-Bench | — | 57.3% |
| APEX-Agents | 40.9% | — |
| τ²-bench Banking | — | 18% |
| ExploitBench | 18.1% | — |
| GBAEval | 0% | — |
| LMArena Search | — | 1189 |

## Reasoning

- GLM-5.1: 38.2 (#57)
- Grok 4.20 (Non-Reasoning): 52.2 (#30)

| Benchmark | GLM-5.1 | Grok 4.20 (Non-Reasoning) |
|---|---|---|
| NYT Connections (extended) | 77.7% | 85.4% |
| Chess Puzzles | 19% | 24% |
| Thematic Generalization | 69.8% | 63.8% |
| LMArena Hard Prompts | 1472 | 1451 |
| Epoch Capabilities Index | 149.86 | 152.01 |
| ARC-AGI-2 | — | 65.1% |
| SimpleBench | 55.1% | — |
| Kagi LLM Benchmark | — | 75% |
| ARC-AGI-1 | — | 89.5% |
| CritPt | 4.6% | — |
| DTBench | — | 90.1% |
| LMCA | — | 38.7% |
| ForecastBench | — | 61.4 |

## Math

- GLM-5.1: 49.0 (#48)
- Grok 4.20 (Non-Reasoning): 48.0 (#54)

| Benchmark | GLM-5.1 | Grok 4.20 (Non-Reasoning) |
|---|---|---|
| FrontierMath (Tiers 1-3) | 36.8% | 44.9% |
| OTIS Mock AIME 2024-2025 | 93.3% | 92.2% |
| ProofBench | 22.2% | 14% |
| LMArena Math | 1472 | 1455 |
| FrontierMath Tier 4 | — | 17.1% |
| MathArena Final-Answer Competitions | 67.1% | — |
| FrontierMath (Feb 2025 set) | 33.4% | — |
| FrontierMath Tier 4 (v1) | 12.5% | — |

## Knowledge

- GLM-5.1: 55.0 (#45)
- Grok 4.20 (Non-Reasoning): 52.8 (#54)

| Benchmark | GLM-5.1 | Grok 4.20 (Non-Reasoning) |
|---|---|---|
| GPQA Diamond | 89.9% | 89.3% |
| SimpleQA Verified | 34% | 30.2% |
| LMArena Expert | 1477 | 1440 |

## Multimodal

- GLM-5.1: —
- Grok 4.20 (Non-Reasoning): 33.2 (#88)

| Benchmark | GLM-5.1 | Grok 4.20 (Non-Reasoning) |
|---|---|---|
| LMArena Vision | — | 1263 |
| Blueprint-Bench 2 | — | 0% |
| LMArena Document | — | 1416 |

## Multilingual

- GLM-5.1: 55.2 (#34)
- Grok 4.20 (Non-Reasoning): 54.7 (#38)

| Benchmark | GLM-5.1 | Grok 4.20 (Non-Reasoning) |
|---|---|---|
| LMArena Non-English | 1448 | 1440 |
| LMArena Chinese | 1516 | 1481 |
| LMArena French | 1478 | 1477 |
| LMArena German | 1466 | 1463 |
| LMArena Japanese | 1436 | 1450 |
| LMArena Korean | 1423 | 1417 |
| LMArena Russian | 1453 | 1457 |
| LMArena Spanish | 1467 | 1442 |

## Instruction Following

- GLM-5.1: 76.5 (#41)
- Grok 4.20 (Non-Reasoning): 75.0 (#79)

| Benchmark | GLM-5.1 | Grok 4.20 (Non-Reasoning) |
|---|---|---|
| LMArena Instruction Following | 1451 | 1420 |

## Long Context

- GLM-5.1: 44.9 (#51)
- Grok 4.20 (Non-Reasoning): 45.4 (#33)

| Benchmark | GLM-5.1 | Grok 4.20 (Non-Reasoning) |
|---|---|---|
| LMArena Longer Query | 1467 | 1436 |
| CL-bench | — | 22.2% |
| CL-bench Life | — | 11.9% |

## Writing & Preference

- GLM-5.1: 67.2 (#29)
- Grok 4.20 (Non-Reasoning): 65.9 (#42)

| Benchmark | GLM-5.1 | Grok 4.20 (Non-Reasoning) |
|---|---|---|
| LMArena Text | 1462 | 1451 |
| LMArena Creative Writing | 1454 | 1439 |
| EQ-Bench Creative Writing | 1592 | 1574 |
| LMArena Multi-Turn | 1473 | 1456 |

## FAQ

### Is GLM-5.1 better than Grok 4.20 (Non-Reasoning)?

GLM-5.1 and Grok 4.20 (Non-Reasoning) score almost the same on the Noometry Index (47.6 vs 48.5), so choose on price, context window or the category you care about most.

### Which is cheaper, GLM-5.1 or Grok 4.20 (Non-Reasoning)?

Grok 4.20 (Non-Reasoning) is cheaper. It lists at $1.25 per million input tokens and $2.50 per million output tokens; GLM-5.1 lists at $1.40 and $4.40.

### Is GLM-5.1 or Grok 4.20 (Non-Reasoning) better for coding?

GLM-5.1 scores higher on coding benchmarks: 48.5 versus 41.8 in the Noometry coding category.

### Which has the bigger context window?

Grok 4.20 (Non-Reasoning) does, with 1M tokens against 200K.

### How many benchmarks do GLM-5.1 and Grok 4.20 (Non-Reasoning) share?

31 benchmarks have published results for both models. GLM-5.1 has 41 scored results on Noometry and Grok 4.20 (Non-Reasoning) has 46.