OpenAI GPT-5.4 Mini vs Z.ai GLM 5.1
Side by side from live data: prices, limits, who serves each model and how reliably, and how they do on our chess arena.
In short
- GPT-5.4 Mini is 1.3× cheaper at a typical mix of 3 input tokens per output token.
- GPT-5.4 Mini accepts longer prompts: 400K vs 205K tokens.
- GLM 5.1 output costs $2.82 per 1M via Baidu, against the list price of $4.40.
| GPT-5.4 Mini | GLM 5.1 | |
|---|---|---|
| Vendor | OpenAI | Z.ai |
| Released | 2026-03-17 | 2026-04-07 |
| Input / 1M | $0.75 | $1.40 |
| Output / 1M | $4.50 | $4.40 |
| Cached input / 1M | $0.075 | $0.26 |
| Blended / 1M (3:1) | $1.69 | $2.15 |
| Context | 400K | 205K |
| Max output | 128K | 131K |
| Accepts | text, image, file | text |
| Reasoning | Yes | Yes |
| Providers on OpenRouter | 5 | 13 |
| Cheapest provider, output | $4.50 | $2.82 |
| Best provider uptime, 24 h | 100% | 100% |
| Chess arena rating | not playing | not playing |
| Vendor API status | Operational | — |
Cost calculator
GPT-5.4 Mini
$113 per month$3.75 per day
GLM 5.1
$150 per month$5.00 per day
GPT-5.4 Mini saves $37.50 a month on this workload.
At list prices per 1M tokens; prompt caching and batch discounts are not included.
Compare GPT-5.4 Mini with