# Claude Sonnet 5.5 vs GLM-5.3

> Claude Sonnet 5.5 is the stronger model overall, scoring 61.9 to 54.8 on the Noometry Index. GLM-5.3 costs 1.9× less per token, which makes it the better buy when Claude Sonnet 5.5's lead doesn't matter for your workload.

- Canonical page: https://noometry.com/compare/claude-sonnet-5-5-vs-glm-5-3
- Last updated: 2026-10-10
- Shared benchmarks: 29

## Summary

- They share 29 benchmarks with published results for both. Claude Sonnet 5.5 scores higher in 7 categories and GLM-5.3 in 2 categories; 6 gaps are clear of the uncertainty.
- The widest gap is in math, where Claude Sonnet 5.5 leads 87.9 to 62.3.
- The biggest single-benchmark swing is FrontierMath Tier 4: 80.5% for Claude Sonnet 5.5 and 29.3% for GLM-5.3.
- GLM-5.3 is cheaper at $1.40 / $4.40 per million input/output tokens, against $2 / $10 for Claude Sonnet 5.5.
- GLM-5.3 has downloadable open weights; the other is API-only.

## Snapshot

| | Claude Sonnet 5.5 | GLM-5.3 |
|---|---|---|
| Provider | Anthropic | Z.ai (Zhipu) |
| Noometry Index | 61.9 | 54.8 |
| Rank | 10 | 26 |
| Context | 1M | 1M |
| Input $/M | $2 | $1.40 |
| Output $/M | $10 | $4.40 |
| Weights | Proprietary | Open |

## Coding

- Claude Sonnet 5.5: 67.3 (#6)
- GLM-5.3: 59.5 (#14)

| Benchmark | Claude Sonnet 5.5 | GLM-5.3 |
|---|---|---|
| FrontierCode | 52.1% | 40.1% |
| CursorBench | 55.5% | 42.6% |
| LMArena WebDev | 1774 | 1622 |
| FrontierSWE | 61.9% | 30.2% |
| SciCode | 61% | 59% |
| LMArena Coding | 1513 | 1496 |
| ALE-Bench | 1,819 | 1,317 |
| DeepSWE | — | 69% |
| WeirdML | — | 75.4% |

## Agentic & Tool Use

- Claude Sonnet 5.5: 45.0 (#16)
- GLM-5.3: 36.4 (#38)

| Benchmark | Claude Sonnet 5.5 | GLM-5.3 |
|---|---|---|
| APEX-Agents | 75.5% | 56.6% |
| Vending-Bench 2 | — | 8,164 |

## Reasoning

- Claude Sonnet 5.5: 54.0 (#28)
- GLM-5.3: 46.1 (#46)

| Benchmark | Claude Sonnet 5.5 | GLM-5.3 |
|---|---|---|
| NYT Connections (extended) | 80.5% | 74.2% |
| CritPt | 31.4% | 19.1% |
| LMArena Hard Prompts | 1495 | 1489 |
| Mystery Game Puzzles | 65% | 33% |
| Epoch Capabilities Index | 165.03 | 155.61 |
| Chess Puzzles | — | 21% |
| DTBench | — | 87.7% |
| LMCA | — | 55.5% |
| Bench to the Future 3 | — | 0.15 |

## Math

- Claude Sonnet 5.5: 87.9 (#6)
- GLM-5.3: 62.3 (#33)

| Benchmark | Claude Sonnet 5.5 | GLM-5.3 |
|---|---|---|
| FrontierMath (Tiers 1-3) | 88.8% | 68.8% |
| FrontierMath Tier 4 | 80.5% | 29.3% |
| OTIS Mock AIME 2024-2025 | 100% | 91.1% |
| ProofBench | 100% | 49% |
| LMArena Math | 1510 | 1489 |
| FrontierMath Erdős | 2.9% | — |

## Knowledge

- Claude Sonnet 5.5: 66.0 (#12)
- GLM-5.3: 58.3 (#37)

| Benchmark | Claude Sonnet 5.5 | GLM-5.3 |
|---|---|---|
| GPQA Diamond | 95.6% | 90.9% |
| SimpleQA Verified | 46.5% | 41% |
| LMArena Expert | 1540 | 1516 |

## Multimodal

- Claude Sonnet 5.5: 51.5 (#6)
- GLM-5.3: —

| Benchmark | Claude Sonnet 5.5 | GLM-5.3 |
|---|---|---|
| LMArena Vision | 1289 | — |
| Furniture Assembly | 75% | — |

## Multilingual

- Claude Sonnet 5.5: 55.3 (#30)
- GLM-5.3: 55.7 (#28)

| Benchmark | Claude Sonnet 5.5 | GLM-5.3 |
|---|---|---|
| LMArena Non-English | 1452 | 1457 |
| LMArena Chinese | 1522 | 1528 |
| LMArena Russian | 1451 | 1463 |
| LMArena French | — | 1499 |
| LMArena German | — | 1499 |
| LMArena Japanese | — | 1453 |
| LMArena Korean | — | 1472 |
| LMArena Spanish | — | 1460 |

## Instruction Following

- Claude Sonnet 5.5: 78.3 (#11)
- GLM-5.3: 77.5 (#23)

| Benchmark | Claude Sonnet 5.5 | GLM-5.3 |
|---|---|---|
| LMArena Instruction Following | 1495 | 1477 |

## Long Context

- Claude Sonnet 5.5: 45.9 (#28)
- GLM-5.3: 45.4 (#41)

| Benchmark | Claude Sonnet 5.5 | GLM-5.3 |
|---|---|---|
| LMArena Longer Query | 1498 | 1482 |

## Writing & Preference

- Claude Sonnet 5.5: 66.0 (#40)
- GLM-5.3: 75.7 (#6)

| Benchmark | Claude Sonnet 5.5 | GLM-5.3 |
|---|---|---|
| LMArena Text | 1471 | 1471 |
| LMArena Creative Writing | 1465 | 1457 |
| LMArena Multi-Turn | 1474 | 1472 |
| EQ-Bench Creative Writing | — | 2075 |

## FAQ

### Is Claude Sonnet 5.5 better than GLM-5.3?

Claude Sonnet 5.5 is the stronger model overall, scoring 61.9 to 54.8 on the Noometry Index. GLM-5.3 costs 1.9× less per token, which makes it the better buy when Claude Sonnet 5.5's lead doesn't matter for your workload.

### Which is cheaper, Claude Sonnet 5.5 or GLM-5.3?

GLM-5.3 is cheaper. It lists at $1.40 per million input tokens and $4.40 per million output tokens; Claude Sonnet 5.5 lists at $2 and $10.

### Is Claude Sonnet 5.5 or GLM-5.3 better for coding?

Claude Sonnet 5.5 scores higher on coding benchmarks: 67.3 versus 59.5 in the Noometry coding category.

### Which has the bigger context window?

Both accept 1M tokens.

### How many benchmarks do Claude Sonnet 5.5 and GLM-5.3 share?

29 benchmarks have published results for both models. Claude Sonnet 5.5 has 32 scored results on Noometry and GLM-5.3 has 42.