Head to head
Z.ai: GLM 5 vs OpenAI: GPT-5.6 Luna
Live prices, context windows, capabilities, and measured quality — updated continuously.
Side by side
| Metric | Z.ai: GLM 5 Z Ai | OpenAI: GPT-5.6 Luna Openai |
|---|---|---|
| Input $/M tokens | $0.600 | $0.100 |
| Output $/M tokens | $1.92 | $0.600 |
| Context window | 205K | 1.1M |
| Max output | 128K | 128K |
| WM Score | 81 | 82 |
| Benchmark quality | 77.6 | 75.7 |
| Hosts serving it | 8 | 3 |
| Throughput (tok/s) | 72 | 129.5 |
| Latency (ms) | 1016 | 649 |
| Vision | ||
| Tools | ||
| Reasoning | ||
| JSON mode |
Which should you pick?
OpenAI: GPT-5.6 Luna costs less per million input tokens — about 6.0× cheaper than Z.ai: GLM 5. Z.ai: GLM 5 scores higher on measured quality. OpenAI: GPT-5.6 Luna takes a larger context window, which matters for long documents or big codebases. Prices here are live list prices; the same model can cost less on a different host, so check the model page for the cheapest offering.