Claude Sonnet 4.6 vs GLM-5.1
Claude Sonnet 4.6 and GLM-5.1 are both current production-tier models. GLM-5.1 is meaningfully cheaper at $1 / $3.2 per 1M. Claude Sonnet 4.6 has a 1M context window — about 5× the 200k of GLM-5.1. Claude Sonnet 4.6 leads on long-context retrieval, instruction following, tool use. GLM-5.1 leads on multilingual.
Specs side by side
| Metric | Anthropic Claude Sonnet 4.6 | Z.ai GLM-5.1 |
|---|---|---|
| Input price (per 1M) | $3 | $1 |
| Output price (per 1M) | $15 | $3.2 |
| Context window | 1M tokens | 200k tokens |
| Speed tier | balanced | balanced |
| Open weights | No | Yes |
| EU region | Yes | No |
| Free tier | No | bigmodel.cn |
| Prompt caching | Yes | No |
| Vision input | Yes | No |
| Extended thinking | Yes | Yes |
When to choose each
Choose Claude Sonnet 4.6 if…
- You need 1M context (5× more than GLM-5.1)
- EU data residency is required
- HIPAA eligibility is required
- You need image input / vision
- Long-context retrieval is central to your workload
- Instruction following is central to your workload
Choose GLM-5.1 if…
- Cost is a priority ($1 / $3.2 per 1M vs $3 / $15 per 1M)
- You need open weights for self-hosting or fine-tuning
- You want a free tier for prototyping
- Multilingual is central to your workload
Benchmark delta
Claude Sonnet 4.6 leads on
- Long-context retrieval
- Instruction following
- Tool use
GLM-5.1 leads on
- Multilingual
FAQ — Claude Sonnet 4.6 vs GLM-5.1
Claude Sonnet 4.6 vs GLM-5.1 — which is better?
Claude Sonnet 4.6 and GLM-5.1 are both current production-tier models. GLM-5.1 is meaningfully cheaper at $1 / $3.2 per 1M. Claude Sonnet 4.6 has a 1M context window — about 5× the 200k of GLM-5.1. Claude Sonnet 4.6 leads on long-context retrieval, instruction following, tool use. GLM-5.1 leads on multilingual. The right pick depends on your use case — see "When to choose each" above for a data-driven decision.
How does Claude Sonnet 4.6 pricing compare to GLM-5.1?
Claude Sonnet 4.6 costs $3 / $15 per 1M vs GLM-5.1 at $1 / $3.2 per 1M. GLM-5.1 is cheaper on output tokens by roughly 369%. Both support prompt caching, which reduces effective cost by 80-90% on repeat system prompts.
Does Claude Sonnet 4.6 or GLM-5.1 have the bigger context window?
Claude Sonnet 4.6 has a 1M-token context window — 5× the 200k context of GLM-5.1. Enough for entire codebases, books, or multi-document RAG.
Is there a free tier for Claude Sonnet 4.6 or GLM-5.1?
Claude Sonnet 4.6: no — Free via Claude.ai web chat; API requires paid credits. GLM-5.1: yes — Free tier with monthly token allowance.
Which is better for coding — Claude Sonnet 4.6 or GLM-5.1?
Claude Sonnet 4.6 leads on coding benchmarks (Claude Sonnet 4.6: 94/100, GLM-5.1: 93/100). For production coding agents also weigh tool-use performance — Claude Sonnet 4.6 scores 96, GLM-5.1 scores 86.