GLM-5.2 vs GPT-5.6 Luna
GLM-5.2 and GPT-5.6 Luna are both current production-tier models. GLM-5.2 is meaningfully cheaper at $1.4 / $4.4 per 1M. GLM-5.2 leads on coding, reasoning, multilingual.
Specs side by side
| Metric | Z.ai GLM-5.2 | OpenAI GPT-5.6 Luna |
|---|---|---|
| Input price (per 1M) | $1.4 | $1 |
| Output price (per 1M) | $4.4 | $6 |
| Context window | 1M tokens | 1.1M tokens |
| Speed tier | balanced | fast |
| Open weights | Yes | No |
| EU region | No | Yes |
| Free tier | bigmodel.cn | No |
| Prompt caching | Yes | Yes |
| Vision input | No | Yes |
| Extended thinking | Yes | Yes |
When to choose each
Choose GLM-5.2 if…
- You need open weights for self-hosting or fine-tuning
- You want a free tier for prototyping
- Coding is central to your workload
- Reasoning is central to your workload
Choose GPT-5.6 Luna if…
- EU data residency is required
- HIPAA eligibility is required
- You need image input / vision
Benchmark delta
GLM-5.2 leads on
- Coding
- Reasoning
- Multilingual
GPT-5.6 Luna leads on
GPT-5.6 Luna has no meaningful benchmark lead in this pair.
FAQ — GLM-5.2 vs GPT-5.6 Luna
GLM-5.2 vs GPT-5.6 Luna — which is better?
GLM-5.2 and GPT-5.6 Luna are both current production-tier models. GLM-5.2 is meaningfully cheaper at $1.4 / $4.4 per 1M. GLM-5.2 leads on coding, reasoning, multilingual. The right pick depends on your use case — see "When to choose each" above for a data-driven decision.
How does GLM-5.2 pricing compare to GPT-5.6 Luna?
GLM-5.2 costs $1.4 / $4.4 per 1M vs GPT-5.6 Luna at $1 / $6 per 1M. GLM-5.2 is cheaper on output tokens by roughly 36%. Both support prompt caching, which reduces effective cost by 80-90% on repeat system prompts.
Does GLM-5.2 or GPT-5.6 Luna have the bigger context window?
GPT-5.6 Luna has a 1.1M-token context window — 1× the 1M context of GLM-5.2. Enough for entire codebases, books, or multi-document RAG.
Is there a free tier for GLM-5.2 or GPT-5.6 Luna?
GLM-5.2: yes — Free tier with monthly token allowance. GPT-5.6 Luna: no — Low-cost at $1/$6 per 1M; starter credits only.
Which is better for coding — GLM-5.2 or GPT-5.6 Luna?
GLM-5.2 leads on coding benchmarks (GLM-5.2: 93/100, GPT-5.6 Luna: 85/100). For production coding agents also weigh tool-use performance — GLM-5.2 scores 86, GPT-5.6 Luna scores 87.