# GLM-4.5-Air vs o4-mini

> o4-mini is the stronger model overall, scoring 41.6 to 38.7 on the Noometry Index. GLM-4.5-Air costs 4.5× less per token, which makes it the better buy when o4-mini's lead doesn't matter for your workload.

- Canonical page: https://noometry.com/compare/glm-4-5-air-vs-o4-mini
- Last updated: 2026-10-10
- Shared benchmarks: 27

## Summary

- They share 27 benchmarks with published results for both. GLM-4.5-Air scores higher in 2 categories and o4-mini in 6 categories; 8 gaps are clear of the uncertainty.
- The widest gap is in knowledge, where o4-mini leads 43.5 to 34.6.
- The biggest single-benchmark swing is Omni-MATH: 39.1% for GLM-4.5-Air and 72% for o4-mini.
- GLM-4.5-Air is cheaper at $0.20 / $1.10 per million input/output tokens, against $1.10 / $4.40 for o4-mini.
- o4-mini accepts more context: 200K tokens versus 131K.
- GLM-4.5-Air has downloadable open weights; the other is API-only.

## Snapshot

| | GLM-4.5-Air | o4-mini |
|---|---|---|
| Provider | Z.ai (Zhipu) | OpenAI |
| Noometry Index | 38.7 | 41.6 |
| Rank | 169 | 119 |
| Context | 131K | 200K |
| Input $/M | $0.20 | $1.10 |
| Output $/M | $1.10 | $4.40 |
| Weights | Open | Proprietary |

## Coding

- GLM-4.5-Air: 34.5 (#225)
- o4-mini: 41.6 (#110)

| Benchmark | GLM-4.5-Air | o4-mini |
|---|---|---|
| GSO | 2.9% | 3.6% |
| LMArena Coding | 1397 | 1369 |
| SWE-bench Verified (bash only) | — | 45% |
| Aider Polyglot | — | 72% |
| WeirdML | — | 52.6% |
| CadEval | — | 62% |
| ALE-Bench | — | 826.17 |
| AlgoTune | — | 1.72 |

## Agentic & Tool Use

- GLM-4.5-Air: —
- o4-mini: 32.3 (#57)

| Benchmark | GLM-4.5-Air | o4-mini |
|---|---|---|
| Berkeley Function Calling Leaderboard | — | 53.2% |
| GDPval | — | 25.3% |
| METR Time Horizons | — | 63.9% |

## Reasoning

- GLM-4.5-Air: 23.3 (#166)
- o4-mini: 24.6 (#143)

| Benchmark | GLM-4.5-Air | o4-mini |
|---|---|---|
| Kagi LLM Benchmark | 43% | 67.6% |
| LMArena Hard Prompts | 1379 | 1351 |
| ForecastBench | 59.2 | 61.8 |
| ARC-AGI-2 | — | 6.1% |
| SimpleBench | — | 38.7% |
| ARC-AGI-1 | — | 58.7% |
| CritPt | — | 0.6% |
| Chess Puzzles | — | 26% |
| EnigmaEval | — | 9.2% |
| Mystery Game Puzzles | — | 5% |
| DTBench | — | 77.6% |
| LMCA | — | 26.5% |
| Epoch Capabilities Index | — | 145.63 |

## Math

- GLM-4.5-Air: 33.8 (#166)
- o4-mini: 40.2 (#79)

| Benchmark | GLM-4.5-Air | o4-mini |
|---|---|---|
| Omni-MATH | 39.1% | 72% |
| LMArena Math | 1396 | 1390 |
| FrontierMath (Tiers 1-3) | — | 36.1% |
| FrontierMath Tier 4 | — | 4.9% |
| OTIS Mock AIME 2024-2025 | — | 81.7% |
| MATH Level 5 | — | 97.8% |
| FrontierMath (Feb 2025 set) | — | 24.8% |
| FrontierMath Tier 4 (v1) | — | 6.3% |

## Knowledge

- GLM-4.5-Air: 34.6 (#184)
- o4-mini: 43.5 (#83)

| Benchmark | GLM-4.5-Air | o4-mini |
|---|---|---|
| Humanity's Last Exam | 8.1% | 18.1% |
| MMLU-Pro | 76.2% | 82% |
| Vectara Hallucination Rate | 9.3% | 18.6% |
| GPQA (HELM) | 59.4% | 73.5% |
| LMArena Expert | 1370 | 1344 |
| GPQA Diamond | — | 79.6% |
| SimpleQA Verified | — | 19.6% |
| Confabulations | — | 15.8% |

## Multimodal

- GLM-4.5-Air: —
- o4-mini: 39.5 (#46)

| Benchmark | GLM-4.5-Air | o4-mini |
|---|---|---|
| LMArena Vision | — | 1194 |
| GeoBench | — | 64% |
| VPCT | — | 57.5% |

## Multilingual

- GLM-4.5-Air: 49.4 (#130)
- o4-mini: 47.2 (#149)

| Benchmark | GLM-4.5-Air | o4-mini |
|---|---|---|
| LMArena Non-English | 1366 | 1336 |
| LMArena Chinese | 1427 | 1355 |
| LMArena French | 1399 | 1362 |
| LMArena German | 1376 | 1336 |
| LMArena Japanese | 1348 | 1308 |
| LMArena Korean | 1306 | 1313 |
| LMArena Russian | 1373 | 1334 |
| LMArena Spanish | 1385 | 1346 |

## Instruction Following

- GLM-4.5-Air: 69.8 (#165)
- o4-mini: 75.4 (#63)

| Benchmark | GLM-4.5-Air | o4-mini |
|---|---|---|
| IFEval | 81.2% | 92.8% |
| LMArena Instruction Following | 1353 | 1321 |

## Long Context

- GLM-4.5-Air: 41.6 (#130)
- o4-mini: 45.5 (#31)

| Benchmark | GLM-4.5-Air | o4-mini |
|---|---|---|
| LMArena Longer Query | 1367 | 1315 |
| Fiction.LiveBench | — | 77.8% |

## Writing & Preference

- GLM-4.5-Air: 56.1 (#134)
- o4-mini: 54.2 (#148)

| Benchmark | GLM-4.5-Air | o4-mini |
|---|---|---|
| LMArena Text | 1384 | 1353 |
| LMArena Creative Writing | 1343 | 1294 |
| WildBench | 78.9% | 85.4% |
| LMArena Multi-Turn | 1371 | 1350 |
| Short-Story Creative Writing | — | 75% |

## FAQ

### Is GLM-4.5-Air better than o4-mini?

o4-mini is the stronger model overall, scoring 41.6 to 38.7 on the Noometry Index. GLM-4.5-Air costs 4.5× less per token, which makes it the better buy when o4-mini's lead doesn't matter for your workload.

### Which is cheaper, GLM-4.5-Air or o4-mini?

GLM-4.5-Air is cheaper. It lists at $0.20 per million input tokens and $1.10 per million output tokens; o4-mini lists at $1.10 and $4.40.

### Is GLM-4.5-Air or o4-mini better for coding?

o4-mini scores higher on coding benchmarks: 41.6 versus 34.5 in the Noometry coding category.

### Which has the bigger context window?

o4-mini does, with 200K tokens against 131K.

### How many benchmarks do GLM-4.5-Air and o4-mini share?

27 benchmarks have published results for both models. GLM-4.5-Air has 27 scored results on Noometry and o4-mini has 60.