# GLM-4.5-Air vs Step 5 Preview

> Step 5 Preview is the stronger model overall, scoring 47.9 to 38.9 on the Noometry Index. GLM-4.5-Air costs 3.4× less per token, which makes it the better buy when Step 5 Preview's lead doesn't matter for your workload.

- Canonical page: https://noometry.com/compare/glm-4-5-air-vs-step-5-preview
- Last updated: 2026-10-11
- Shared benchmarks: 13

## Summary

- They share 13 benchmarks with published results for both. GLM-4.5-Air scores higher in 0 categories and Step 5 Preview in 8 categories; 8 gaps are clear of the uncertainty.
- The widest gap is in coding, where Step 5 Preview leads 51.8 to 33.3.
- GLM-4.5-Air is cheaper at $0.20 / $1.10 per million input/output tokens, against $1 / $2.70 for Step 5 Preview.
- Step 5 Preview accepts more context: 1.02M tokens versus 131K.
- GLM-4.5-Air has downloadable open weights; the other is API-only.

## Snapshot

| | GLM-4.5-Air | Step 5 Preview |
|---|---|---|
| Provider | Z.ai (Zhipu) | StepFun |
| Noometry Index | 38.9 | 47.9 |
| Rank | 177 | 58 |
| Context | 131K | 1.02M |
| Input $/M | $0.20 | $1 |
| Output $/M | $1.10 | $2.70 |
| Weights | Open | Proprietary |

## Coding

- GLM-4.5-Air: 33.3 (#259)
- Step 5 Preview: 51.8 (#36)

| Benchmark | GLM-4.5-Air | Step 5 Preview |
|---|---|---|
| LMArena Coding | 1397 | 1480 |
| LMArena WebDev | — | 1564 |
| SciCode | — | 58.9% |
| GSO | 2.9% | — |

## Reasoning

- GLM-4.5-Air: 24.1 (#166)
- Step 5 Preview: 40.0 (#57)

| Benchmark | GLM-4.5-Air | Step 5 Preview |
|---|---|---|
| LMArena Hard Prompts | 1379 | 1465 |
| Kagi LLM Benchmark | 43% | — |
| CritPt | — | 20.9% |
| ForecastBench | 59.2 | — |

## Math

- GLM-4.5-Air: 36.2 (#170)
- Step 5 Preview: 46.1 (#72)

| Benchmark | GLM-4.5-Air | Step 5 Preview |
|---|---|---|
| LMArena Math | 1396 | 1470 |
| ProofBench | — | 42% |
| Omni-MATH | 39.1% | — |

## Knowledge

- GLM-4.5-Air: 35.0 (#191)
- Step 5 Preview: 41.2 (#112)

| Benchmark | GLM-4.5-Air | Step 5 Preview |
|---|---|---|
| LMArena Expert | 1370 | 1470 |
| Humanity's Last Exam | 8.1% | — |
| MMLU-Pro | 76.2% | — |
| Vectara Hallucination Rate | 9.3% | — |
| GPQA (HELM) | 59.4% | — |

## Multimodal

- GLM-4.5-Air: —
- Step 5 Preview: 41.0 (#41)

| Benchmark | GLM-4.5-Air | Step 5 Preview |
|---|---|---|
| LMArena Vision | — | 1267 |

## Multilingual

- GLM-4.5-Air: 49.1 (#135)
- Step 5 Preview: 53.8 (#54)

| Benchmark | GLM-4.5-Air | Step 5 Preview |
|---|---|---|
| LMArena Non-English | 1366 | 1432 |
| LMArena Chinese | 1426 | 1519 |
| LMArena Russian | 1373 | 1436 |
| LMArena Spanish | 1386 | 1439 |
| LMArena French | 1399 | — |
| LMArena German | 1377 | — |
| LMArena Japanese | 1348 | — |
| LMArena Korean | 1308 | — |

## Instruction Following

- GLM-4.5-Air: 69.6 (#171)
- Step 5 Preview: 76.0 (#50)

| Benchmark | GLM-4.5-Air | Step 5 Preview |
|---|---|---|
| LMArena Instruction Following | 1354 | 1444 |
| IFEval | 81.2% | — |

## Long Context

- GLM-4.5-Air: 41.6 (#135)
- Step 5 Preview: 44.5 (#64)

| Benchmark | GLM-4.5-Air | Step 5 Preview |
|---|---|---|
| LMArena Longer Query | 1366 | 1455 |

## Writing & Preference

- GLM-4.5-Air: 55.9 (#139)
- Step 5 Preview: 62.8 (#71)

| Benchmark | GLM-4.5-Air | Step 5 Preview |
|---|---|---|
| LMArena Text | 1384 | 1442 |
| LMArena Creative Writing | 1343 | 1410 |
| LMArena Multi-Turn | 1371 | 1447 |
| WildBench | 78.9% | — |

## FAQ

### Is GLM-4.5-Air better than Step 5 Preview?

Step 5 Preview is the stronger model overall, scoring 47.9 to 38.9 on the Noometry Index. GLM-4.5-Air costs 3.4× less per token, which makes it the better buy when Step 5 Preview's lead doesn't matter for your workload.

### Which is cheaper, GLM-4.5-Air or Step 5 Preview?

GLM-4.5-Air is cheaper. It lists at $0.20 per million input tokens and $1.10 per million output tokens; Step 5 Preview lists at $1 and $2.70.

### Is GLM-4.5-Air or Step 5 Preview better for coding?

Step 5 Preview scores higher on coding benchmarks: 51.8 versus 33.3 in the Noometry coding category.

### Which has the bigger context window?

Step 5 Preview does, with 1.02M tokens against 131K.

### How many benchmarks do GLM-4.5-Air and Step 5 Preview share?

13 benchmarks have published results for both models. GLM-4.5-Air has 27 scored results on Noometry and Step 5 Preview has 18.