# GLM-4.5 vs GPT-5-Codex

> GLM-4.5 is the stronger model overall, scoring 41.4 to 37.3 on the Noometry Index.

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

## Summary

- They share 2 benchmarks with published results for both. GLM-4.5 scores higher in 0 categories and GPT-5-Codex in 2 categories; one gap is clear of the uncertainty.
- The biggest single-benchmark swing is WeirdML: 40.6% for GLM-4.5 and 54.5% for GPT-5-Codex.
- GLM-4.5 is cheaper at $0.60 / $2.20 per million input/output tokens, against $1.25 / $10 for GPT-5-Codex.
- GPT-5-Codex accepts more context: 400K tokens versus 131K.
- GLM-4.5 has downloadable open weights; the other is API-only.

## Snapshot

| | GLM-4.5 | GPT-5-Codex |
|---|---|---|
| Provider | Z.ai (Zhipu) | OpenAI |
| Noometry Index | 41.4 | 37.3 |
| Rank | 125 | 190 |
| Context | 131K | 400K |
| Input $/M | $0.60 | $1.25 |
| Output $/M | $2.20 | $10 |
| Weights | Open | Proprietary |

## Coding

- GLM-4.5: 41.1 (#121)
- GPT-5-Codex: 41.9 (#100)

| Benchmark | GLM-4.5 | GPT-5-Codex |
|---|---|---|
| WeirdML | 40.6% | 54.5% |
| SWE-bench Verified (bash only) | 54.2% | — |
| LMArena Coding | 1434 | — |
| ALE-Bench | 344.82 | — |
| AlgoTune | 1.52 | — |

## Agentic & Tool Use

- GLM-4.5: —
- GPT-5-Codex: 30.8 (#66)

| Benchmark | GLM-4.5 | GPT-5-Codex |
|---|---|---|
| Terminal-Bench | — | 44.3% |

## Reasoning

- GLM-4.5: 27.7 (#99)
- GPT-5-Codex: 30.0 (#80)

| Benchmark | GLM-4.5 | GPT-5-Codex |
|---|---|---|
| Kagi LLM Benchmark | 57.9% | 70.3% |
| LMArena Hard Prompts | 1430 | — |

## Math

- GLM-4.5: 36.3 (#119)
- GPT-5-Codex: —

| Benchmark | GLM-4.5 | GPT-5-Codex |
|---|---|---|
| LMArena Math | 1427 | — |

## Knowledge

- GLM-4.5: 35.5 (#172)
- GPT-5-Codex: —

| Benchmark | GLM-4.5 | GPT-5-Codex |
|---|---|---|
| Humanity's Last Exam | 8.3% | — |
| Confabulations | 11.3% | — |
| LMArena Expert | 1433 | — |

## Multilingual

- GLM-4.5: 53.0 (#74)
- GPT-5-Codex: —

| Benchmark | GLM-4.5 | GPT-5-Codex |
|---|---|---|
| LMArena Non-English | 1417 | — |
| LMArena Chinese | 1465 | — |
| LMArena French | 1423 | — |
| LMArena German | 1406 | — |
| LMArena Japanese | 1416 | — |
| LMArena Korean | 1382 | — |
| LMArena Russian | 1414 | — |
| LMArena Spanish | 1454 | — |

## Instruction Following

- GLM-4.5: 74.3 (#100)
- GPT-5-Codex: —

| Benchmark | GLM-4.5 | GPT-5-Codex |
|---|---|---|
| LMArena Instruction Following | 1405 | — |

## Long Context

- GLM-4.5: 38.2 (#196)
- GPT-5-Codex: —

| Benchmark | GLM-4.5 | GPT-5-Codex |
|---|---|---|
| Fiction.LiveBench | 58.3% | — |
| LMArena Longer Query | 1413 | — |

## Writing & Preference

- GLM-4.5: 57.7 (#121)
- GPT-5-Codex: —

| Benchmark | GLM-4.5 | GPT-5-Codex |
|---|---|---|
| LMArena Text | 1430 | — |
| LMArena Creative Writing | 1395 | — |
| Short-Story Creative Writing | 73.4% | — |
| EQ-Bench Creative Writing | 1343 | — |
| LMArena Multi-Turn | 1415 | — |

## FAQ

### Is GLM-4.5 better than GPT-5-Codex?

GLM-4.5 is the stronger model overall, scoring 41.4 to 37.3 on the Noometry Index.

### Which is cheaper, GLM-4.5 or GPT-5-Codex?

GLM-4.5 is cheaper. It lists at $0.60 per million input tokens and $2.20 per million output tokens; GPT-5-Codex lists at $1.25 and $10.

### Is GLM-4.5 or GPT-5-Codex better for coding?

They score almost the same on coding (41.1 vs 41.9); test both on your own repository before choosing.

### Which has the bigger context window?

GPT-5-Codex does, with 400K tokens against 131K.

### How many benchmarks do GLM-4.5 and GPT-5-Codex share?

2 benchmarks have published results for both models. GLM-4.5 has 27 scored results on Noometry and GPT-5-Codex has 3.