# Gemini 3.8 Flash vs GLM-5.1

> Gemini 3.8 Flash is the stronger model overall, scoring 61.8 to 47.8 on the Noometry Index.

- Canonical page: https://noometry.com/compare/gemini-3-8-flash-vs-glm-5-1
- Last updated: 2026-10-10
- Shared benchmarks: 33

## Summary

- They share 33 benchmarks with published results for both. Gemini 3.8 Flash scores higher in 9 categories and GLM-5.1 in 0 categories; 9 gaps are clear of the uncertainty.
- The widest gap is in reasoning, where Gemini 3.8 Flash leads 76.9 to 39.1.
- The biggest single-benchmark swing is Chess Puzzles: 61% for Gemini 3.8 Flash and 19% for GLM-5.1.
- Gemini 3.8 Flash is cheaper at $0.75 / $3.75 per million input/output tokens, against $1.40 / $4.40 for GLM-5.1.
- Gemini 3.8 Flash accepts more context: 1.05M tokens versus 200K.
- GLM-5.1 has downloadable open weights; the other is API-only.

## Snapshot

| | Gemini 3.8 Flash | GLM-5.1 |
|---|---|---|
| Provider | Google | Z.ai (Zhipu) |
| Noometry Index | 61.8 | 47.8 |
| Rank | 11 | 59 |
| Context | 1.05M | 200K |
| Input $/M | $0.75 | $1.40 |
| Output $/M | $3.75 | $4.40 |
| Weights | Proprietary | Open |

## Coding

- Gemini 3.8 Flash: 59.2 (#15)
- GLM-5.1: 48.7 (#55)

| Benchmark | Gemini 3.8 Flash | GLM-5.1 |
|---|---|---|
| LMArena WebDev | 1584 | 1508 |
| SciCode | 56.6% | 43.8% |
| WeirdML | 84.8% | 57.1% |
| LMArena Coding | 1510 | 1485 |
| ALE-Bench | 1,270 | 887.1 |
| SWE-bench Verified | — | 74.2% |
| DeepSWE | 73.8% | — |
| FrontierCode | 41.2% | — |
| CursorBench | 39.6% | — |
| FrontierSWE | 19.6% | — |

## Agentic & Tool Use

- Gemini 3.8 Flash: 41.8 (#21)
- GLM-5.1: 24.9 (#113)

| Benchmark | Gemini 3.8 Flash | GLM-5.1 |
|---|---|---|
| APEX-Agents | 64.3% | 40.9% |
| Vending-Bench 2 | 5,094 | 5,634 |
| Remote Labor Index | 5.8% | — |
| ExploitBench | — | 18.1% |
| GBAEval | — | 0% |
| GDP.pdf | 23.4% | — |

## Reasoning

- Gemini 3.8 Flash: 76.9 (#5)
- GLM-5.1: 39.1 (#60)

| Benchmark | Gemini 3.8 Flash | GLM-5.1 |
|---|---|---|
| NYT Connections (extended) | 97.4% | 77.7% |
| CritPt | 18.3% | 4.6% |
| Chess Puzzles | 61% | 19% |
| LMArena Hard Prompts | 1508 | 1472 |
| Epoch Capabilities Index | 156.71 | 149.84 |
| ARC-AGI-2 | 89.2% | — |
| SimpleBench | — | 55.1% |
| ARC-AGI-1 | 98.5% | — |
| Thematic Generalization | — | 69.8% |
| Mystery Game Puzzles | 47% | — |
| DTBench | 95.7% | — |
| LMCA | 52.9% | — |
| Surface Evolver Bench | 76.9% | — |

## Math

- Gemini 3.8 Flash: 65.3 (#28)
- GLM-5.1: 49.7 (#60)

| Benchmark | Gemini 3.8 Flash | GLM-5.1 |
|---|---|---|
| FrontierMath (Tiers 1-3) | 68.4% | 36.8% |
| OTIS Mock AIME 2024-2025 | 98.9% | 93.3% |
| ProofBench | 48% | 22.2% |
| LMArena Math | 1528 | 1473 |
| FrontierMath Tier 4 | 22% | — |
| MathArena Final-Answer Competitions | — | 67.1% |
| FrontierMath (Feb 2025 set) | — | 33.4% |
| FrontierMath Tier 4 (v1) | — | 12.5% |

## Knowledge

- Gemini 3.8 Flash: 74.8 (#2)
- GLM-5.1: 54.9 (#50)

| Benchmark | Gemini 3.8 Flash | GLM-5.1 |
|---|---|---|
| GPQA Diamond | 95.4% | 89.9% |
| SimpleQA Verified | 69.7% | 34% |
| LMArena Expert | 1524 | 1476 |
| Humanity's Last Exam | 44.5% | — |

## Multimodal

- Gemini 3.8 Flash: 40.7 (#45)
- GLM-5.1: —

| Benchmark | Gemini 3.8 Flash | GLM-5.1 |
|---|---|---|
| LMArena Vision | 1314 | — |
| Blueprint-Bench 2 | 38.6% | — |
| Furniture Assembly | 31.7% | — |

## Multilingual

- Gemini 3.8 Flash: 58.0 (#5)
- GLM-5.1: 55.0 (#36)

| Benchmark | Gemini 3.8 Flash | GLM-5.1 |
|---|---|---|
| LMArena Non-English | 1491 | 1447 |
| LMArena Chinese | 1554 | 1515 |
| LMArena French | 1498 | 1474 |
| LMArena German | 1493 | 1465 |
| LMArena Japanese | 1502 | 1434 |
| LMArena Korean | 1459 | 1418 |
| LMArena Russian | 1515 | 1454 |
| LMArena Spanish | 1485 | 1469 |

## Instruction Following

- Gemini 3.8 Flash: 78.0 (#13)
- GLM-5.1: 76.3 (#42)

| Benchmark | Gemini 3.8 Flash | GLM-5.1 |
|---|---|---|
| LMArena Instruction Following | 1490 | 1451 |

## Long Context

- Gemini 3.8 Flash: 46.3 (#24)
- GLM-5.1: 44.9 (#53)

| Benchmark | Gemini 3.8 Flash | GLM-5.1 |
|---|---|---|
| LMArena Longer Query | 1508 | 1466 |

## Writing & Preference

- Gemini 3.8 Flash: 72.2 (#15)
- GLM-5.1: 66.9 (#31)

| Benchmark | Gemini 3.8 Flash | GLM-5.1 |
|---|---|---|
| LMArena Text | 1499 | 1461 |
| LMArena Creative Writing | 1492 | 1453 |
| EQ-Bench Creative Writing | 1748 | 1592 |
| LMArena Multi-Turn | 1501 | 1472 |

## FAQ

### Is Gemini 3.8 Flash better than GLM-5.1?

Gemini 3.8 Flash is the stronger model overall, scoring 61.8 to 47.8 on the Noometry Index.

### Which is cheaper, Gemini 3.8 Flash or GLM-5.1?

Gemini 3.8 Flash is cheaper. It lists at $0.75 per million input tokens and $3.75 per million output tokens; GLM-5.1 lists at $1.40 and $4.40.

### Is Gemini 3.8 Flash or GLM-5.1 better for coding?

Gemini 3.8 Flash scores higher on coding benchmarks: 59.2 versus 48.7 in the Noometry coding category.

### Which has the bigger context window?

Gemini 3.8 Flash does, with 1.05M tokens against 200K.

### How many benchmarks do Gemini 3.8 Flash and GLM-5.1 share?

33 benchmarks have published results for both models. Gemini 3.8 Flash has 50 scored results on Noometry and GLM-5.1 has 41.