Claude Sonnet 4 vs GLM-5.1
Anthropic Claude Sonnet 4 | Z.ai GLM-5.1 | |
|---|---|---|
| Overview | ||
| Company | Anthropic | Z.ai |
| Release date | May 22 2025 | Apr 7 2026 |
| Access | Proprietary | Open Weight |
| Specifications | ||
Parameters | — | 744B |
Context window | — | 200k |
| 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. | 30% | — |
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. | 72.7% | — |
Agentic terminal coding Terminal-Bench 2.0Can the AI work in a command-line terminal — running commands and finishing technical setup tasks the way a developer would? (Version 2.0 of the test.) Higher is better. | — | 63.5% |
Web browsing BrowseCompCan the AI browse the web and track down hard-to-find answers? Higher is better. | — | 68% |
Science GPQA DiamondGraduate-level science questions in biology, physics, and chemistry — hard enough that subject-matter PhDs score around 65%. Higher is better. | 75.4% | 86.2%Best |
| Timeline | ||
| Release gap | Claude Sonnet 4 shipped 320 days before GLM-5.1 | |
Which is better: Claude Sonnet 4 or GLM-5.1?
GLM-5.1 leads Claude Sonnet 4 on 1 of the 1 benchmark they both report (GPQA Diamond). Claude Sonnet 4 shipped 320 days before GLM-5.1, so benchmark comparisons should account for the intervening progress.
Claude Sonnet 4 is proprietary, while GLM-5.1 is open weight.
On GPQA Diamond, GLM-5.1 leads at 86.2% vs Claude Sonnet 4 at 75.4%.
Frequently asked questions
Claude Sonnet 4 was released by Anthropic on May 22 2025.
GLM-5.1 was released by Z.ai on Apr 7 2026.
GLM-5.1 leads on GPQA Diamond — Claude Sonnet 4 75.4% vs GLM-5.1 86.2%.
Claude Sonnet 4 is a proprietary model released by Anthropic. GLM-5.1 is an open weight model released by Z.ai.
Other comparisons
Claude Sonnet 4 vs GPT-5.6 SolGLM-5.1 vs GPT-5.6 SolClaude Sonnet 4 vs Gemini OmniGLM-5.1 vs Gemini OmniClaude Sonnet 4 vs Muse SparkGLM-5.1 vs Muse SparkClaude Sonnet 4 vs Grok 4.3 BetaGLM-5.1 vs Grok 4.3 BetaClaude Sonnet 4 vs DeepSeek-V4-ProGLM-5.1 vs DeepSeek-V4-ProClaude Sonnet 4 vs Mistral Medium 3.5GLM-5.1 vs Mistral Medium 3.5