# GLM-4.5-Air vs Mercury 2

> GLM-4.5-Air and Mercury 2 score almost the same on the Noometry Index (38.7 vs 38.8), so choose on price, context window or the category you care about most.

- Canonical page: https://noometry.com/compare/glm-4-5-air-vs-mercury-2
- Last updated: 2026-10-10
- Shared benchmarks: 12

## Summary

- They share 12 benchmarks with published results for both. GLM-4.5-Air scores higher in 5 categories and Mercury 2 in 2 categories; 5 gaps are clear of the uncertainty.
- Mercury 2 is cheaper at $0.25 / $0.75 per million input/output tokens, against $0.20 / $1.10 for GLM-4.5-Air.
- GLM-4.5-Air accepts more context: 131K tokens versus 128K.
- GLM-4.5-Air has downloadable open weights; the other is API-only.

## Snapshot

| | GLM-4.5-Air | Mercury 2 |
|---|---|---|
| Provider | Z.ai (Zhipu) | Inception |
| Noometry Index | 38.7 | 38.8 |
| Rank | 169 | 167 |
| Context | 131K | 128K |
| Input $/M | $0.20 | $0.25 |
| Output $/M | $1.10 | $0.75 |
| Weights | Open | Proprietary |

## Coding

- GLM-4.5-Air: 34.5 (#225)
- Mercury 2: 33.2 (#250)

| Benchmark | GLM-4.5-Air | Mercury 2 |
|---|---|---|
| LMArena Coding | 1397 | 1391 |
| LMArena WebDev | — | 1170 |
| SciCode | — | 38.7% |
| GSO | 2.9% | — |
| WeirdML | — | 43.2% |
| ALE-Bench | — | 785.58 |

## Reasoning

- GLM-4.5-Air: 23.3 (#166)
- Mercury 2: 23.0 (#170)

| Benchmark | GLM-4.5-Air | Mercury 2 |
|---|---|---|
| LMArena Hard Prompts | 1379 | 1362 |
| Kagi LLM Benchmark | 43% | — |
| CritPt | — | 0.8% |
| ForecastBench | 59.2 | — |

## Math

- GLM-4.5-Air: 33.8 (#166)
- Mercury 2: —

| Benchmark | GLM-4.5-Air | Mercury 2 |
|---|---|---|
| Omni-MATH | 39.1% | — |
| LMArena Math | 1396 | — |

## Knowledge

- GLM-4.5-Air: 34.6 (#184)
- Mercury 2: 35.6 (#170)

| Benchmark | GLM-4.5-Air | Mercury 2 |
|---|---|---|
| Vectara Hallucination Rate | 9.3% | 12.3% |
| LMArena Expert | 1370 | 1358 |
| Humanity's Last Exam | 8.1% | — |
| MMLU-Pro | 76.2% | — |
| GPQA (HELM) | 59.4% | — |

## Multilingual

- GLM-4.5-Air: 49.4 (#130)
- Mercury 2: 46.8 (#153)

| Benchmark | GLM-4.5-Air | Mercury 2 |
|---|---|---|
| LMArena Non-English | 1366 | 1331 |
| LMArena Chinese | 1427 | 1416 |
| LMArena Russian | 1373 | 1303 |
| LMArena French | 1399 | — |
| LMArena German | 1376 | — |
| LMArena Japanese | 1348 | — |
| LMArena Korean | 1306 | — |
| LMArena Spanish | 1385 | — |

## Instruction Following

- GLM-4.5-Air: 69.8 (#165)
- Mercury 2: 70.4 (#161)

| Benchmark | GLM-4.5-Air | Mercury 2 |
|---|---|---|
| LMArena Instruction Following | 1353 | 1328 |
| IFEval | 81.2% | — |

## Long Context

- GLM-4.5-Air: 41.6 (#130)
- Mercury 2: 40.4 (#149)

| Benchmark | GLM-4.5-Air | Mercury 2 |
|---|---|---|
| LMArena Longer Query | 1367 | 1329 |

## Writing & Preference

- GLM-4.5-Air: 56.1 (#134)
- Mercury 2: 54.0 (#151)

| Benchmark | GLM-4.5-Air | Mercury 2 |
|---|---|---|
| LMArena Text | 1384 | 1355 |
| LMArena Creative Writing | 1343 | 1289 |
| LMArena Multi-Turn | 1371 | 1358 |
| WildBench | 78.9% | — |

## FAQ

### Is GLM-4.5-Air better than Mercury 2?

GLM-4.5-Air and Mercury 2 score almost the same on the Noometry Index (38.7 vs 38.8), so choose on price, context window or the category you care about most.

### Which is cheaper, GLM-4.5-Air or Mercury 2?

Mercury 2 is cheaper. It lists at $0.25 per million input tokens and $0.75 per million output tokens; GLM-4.5-Air lists at $0.20 and $1.10.

### Is GLM-4.5-Air or Mercury 2 better for coding?

GLM-4.5-Air scores higher on coding benchmarks: 34.5 versus 33.2 in the Noometry coding category.

### Which has the bigger context window?

GLM-4.5-Air does, with 131K tokens against 128K.

### How many benchmarks do GLM-4.5-Air and Mercury 2 share?

12 benchmarks have published results for both models. GLM-4.5-Air has 27 scored results on Noometry and Mercury 2 has 17.