# GLM-5.2 vs GPT-5.1-Codex

> GLM-5.2 is the stronger model overall, scoring 51.1 to 38.6 on the Noometry Index.

- Canonical page: https://noometry.com/compare/glm-5-2-vs-gpt-5-1-codex
- Last updated: 2026-10-10
- Shared benchmarks: 3

## Summary

- They share 3 benchmarks with published results for both. GLM-5.2 scores higher in 2 categories and GPT-5.1-Codex in 1 category; 3 gaps are clear of the uncertainty.
- The widest gap is in math, where GLM-5.2 leads 55.7 to 30.3.
- The biggest single-benchmark swing is ProofBench: 35% for GLM-5.2 and 9% for GPT-5.1-Codex.
- GLM-5.2 is cheaper at $1.40 / $4.40 per million input/output tokens, against $1.25 / $10 for GPT-5.1-Codex.
- GLM-5.2 accepts more context: 1M tokens versus 400K.
- GLM-5.2 has downloadable open weights; the other is API-only.

## Snapshot

| | GLM-5.2 | GPT-5.1-Codex |
|---|---|---|
| Provider | Z.ai (Zhipu) | OpenAI |
| Noometry Index | 51.1 | 38.6 |
| Rank | 44 | 186 |
| Context | 1M | 400K |
| Input $/M | $1.40 | $1.25 |
| Output $/M | $4.40 | $10 |
| Weights | Open | Proprietary |

## Coding

- GLM-5.2: 51.3 (#41)
- GPT-5.1-Codex: 41.9 (#116)

| Benchmark | GLM-5.2 | GPT-5.1-Codex |
|---|---|---|
| LMArena WebDev | 1603 | 1337 |
| ALE-Bench | 1,047 | 1,245 |
| SWE-bench Verified | 78.7% | — |
| DeepSWE | 43.8% | — |
| FrontierCode | 24.5% | — |
| SWE-bench Verified (bash only) | — | 66% |
| SciCode | 50.5% | — |
| WeirdML | 70.1% | — |
| LMArena Coding | 1485 | — |

## Agentic & Tool Use

- GLM-5.2: 32.4 (#63)
- GPT-5.1-Codex: 38.0 (#33)

| Benchmark | GLM-5.2 | GPT-5.1-Codex |
|---|---|---|
| Terminal-Bench | — | 60.4% |
| APEX-Agents | 45.2% | — |
| τ²-bench Banking | 37.1% | — |
| PostTrainBench | 31.7% | — |
| GBAEval | 0% | — |
| METR Time Horizons | — | 70.8% |
| Vending-Bench 2 | 8,314 | — |

## Reasoning

- GLM-5.2: 42.3 (#52)
- GPT-5.1-Codex: —

| Benchmark | GLM-5.2 | GPT-5.1-Codex |
|---|---|---|
| ARC-AGI-2 | 22.8% | — |
| SimpleBench | 58.8% | — |
| Kagi LLM Benchmark | 62.6% | — |
| NYT Connections (extended) | 74.3% | — |
| ARC-AGI-1 | 77% | — |
| CritPt | 20.9% | — |
| Chess Puzzles | 21% | — |
| EBR-Bench | 9.5% | — |
| LMArena Hard Prompts | 1480 | — |
| Mystery Game Puzzles | 19% | — |
| DTBench | 93.6% | — |
| LMCA | 45.8% | — |
| Surface Evolver Bench | 55.6% | — |
| Epoch Capabilities Index | 151.78 | — |

## Math

- GLM-5.2: 55.7 (#43)
- GPT-5.1-Codex: 30.3 (#235)

| Benchmark | GLM-5.2 | GPT-5.1-Codex |
|---|---|---|
| ProofBench | 35% | 9% |
| FrontierMath (Tiers 1-3) | 59.2% | — |
| FrontierMath Tier 4 | 29.3% | — |
| MathArena Final-Answer Competitions | 67.6% | — |
| OTIS Mock AIME 2024-2025 | 86.4% | — |
| LMArena Math | 1482 | — |

## Knowledge

- GLM-5.2: 57.1 (#40)
- GPT-5.1-Codex: —

| Benchmark | GLM-5.2 | GPT-5.1-Codex |
|---|---|---|
| GPQA Diamond | 91.9% | — |
| SimpleQA Verified | 34.2% | — |
| LMArena Expert | 1486 | — |

## Multilingual

- GLM-5.2: 55.8 (#26)
- GPT-5.1-Codex: —

| Benchmark | GLM-5.2 | GPT-5.1-Codex |
|---|---|---|
| LMArena Non-English | 1459 | — |
| LMArena Chinese | 1519 | — |
| LMArena French | 1479 | — |
| LMArena German | 1468 | — |
| LMArena Japanese | 1451 | — |
| LMArena Korean | 1445 | — |
| LMArena Russian | 1466 | — |
| LMArena Spanish | 1477 | — |

## Instruction Following

- GLM-5.2: 76.9 (#34)
- GPT-5.1-Codex: —

| Benchmark | GLM-5.2 | GPT-5.1-Codex |
|---|---|---|
| LMArena Instruction Following | 1465 | — |

## Long Context

- GLM-5.2: 45.3 (#43)
- GPT-5.1-Codex: —

| Benchmark | GLM-5.2 | GPT-5.1-Codex |
|---|---|---|
| LMArena Longer Query | 1479 | — |

## Writing & Preference

- GLM-5.2: 70.4 (#21)
- GPT-5.1-Codex: —

| Benchmark | GLM-5.2 | GPT-5.1-Codex |
|---|---|---|
| LMArena Text | 1470 | — |
| LMArena Creative Writing | 1462 | — |
| EQ-Bench Creative Writing | 1757 | — |
| EQ-Bench 4 | 1222 | — |
| LMArena Multi-Turn | 1469 | — |

## FAQ

### Is GLM-5.2 better than GPT-5.1-Codex?

GLM-5.2 is the stronger model overall, scoring 51.1 to 38.6 on the Noometry Index.

### Which is cheaper, GLM-5.2 or GPT-5.1-Codex?

GLM-5.2 is cheaper. It lists at $1.40 per million input tokens and $4.40 per million output tokens; GPT-5.1-Codex lists at $1.25 and $10.

### Is GLM-5.2 or GPT-5.1-Codex better for coding?

GLM-5.2 scores higher on coding benchmarks: 51.3 versus 41.9 in the Noometry coding category.

### Which has the bigger context window?

GLM-5.2 does, with 1M tokens against 400K.

### How many benchmarks do GLM-5.2 and GPT-5.1-Codex share?

3 benchmarks have published results for both models. GLM-5.2 has 51 scored results on Noometry and GPT-5.1-Codex has 6.