Claude 3.5 Sonnet vs GLM-4.5
Anthropic Claude 3.5 Sonnet | Z.ai GLM-4.5 | |
|---|---|---|
| Overview | ||
| Company | Anthropic | Z.ai |
| Release date | Jun 20 2024 | Jul 28 2025 |
| Access | Proprietary | Open Weight |
| Specifications | ||
Parameters | — | 355B |
Context window | — | 128k |
| Benchmarks | ||
Nonsense detection BullshitBench v2Given a confidently-worded but nonsensical prompt, does the AI spot that it makes no sense and push back — instead of playing along and inventing an answer? The score is how often it clearly called out the nonsense. Higher is better. | 45% | — |
Coding SWE-Bench VerifiedReal coding tasks pulled from open-source projects — the AI has to find and fix actual bugs. A human-checked version of the original SWE-Bench. Higher is better. | 33.4% | 64.2%Best |
Science GPQA DiamondGraduate-level science questions in biology, physics, and chemistry — hard enough that subject-matter PhDs score around 65%. Higher is better. | 59.4% | 79.1%Best |
| Timeline | ||
| Release gap | Claude 3.5 Sonnet shipped 403 days before GLM-4.5 | |
Which is better: Claude 3.5 Sonnet or GLM-4.5?
GLM-4.5 leads Claude 3.5 Sonnet on 2 of the 2 benchmarks they both report (SWE-Bench Verified, GPQA Diamond). Claude 3.5 Sonnet shipped 403 days before GLM-4.5, so benchmark comparisons should account for the intervening progress.
Claude 3.5 Sonnet is proprietary, while GLM-4.5 is open weight.
On SWE-Bench Verified, GLM-4.5 leads at 64.2% vs Claude 3.5 Sonnet at 33.4%. On GPQA Diamond, GLM-4.5 leads at 79.1% vs Claude 3.5 Sonnet at 59.4%.
Frequently asked questions
Claude 3.5 Sonnet was released by Anthropic on Jun 20 2024.
GLM-4.5 was released by Z.ai on Jul 28 2025.
GLM-4.5 leads on SWE-Bench Verified — Claude 3.5 Sonnet 33.4% vs GLM-4.5 64.2%.
GLM-4.5 leads on GPQA Diamond — Claude 3.5 Sonnet 59.4% vs GLM-4.5 79.1%.
Claude 3.5 Sonnet is a proprietary model released by Anthropic. GLM-4.5 is an open weight model released by Z.ai.