Comparison
GPT-5.1 vs GPT-5 mini
How GPT-5.1 and GPT-5 mini compare on the numbers that decide the call - and how to switch between them without touching your code.
| Spec | GPT-5.1 | GPT-5 mini |
|---|---|---|
| Input price / 1Mlower is cheaper | $1.25 | $0.25 |
| Output price / 1Mlower is cheaper | $10 | $2 |
| Context windowbigger fits more | 400K | 400K |
| Typical speedfaster median | 1.4s | 380ms |
| Quality score | 95/100 | 82/100 |
| Provider | OpenAI | OpenAI |
Which should you pick?
- GPT-5 mini is cheaper on input tokens ($0.25 vs $1.25).
- GPT-5 mini is usually the faster to answer.
- GPT-5.1 scores higher on the composite quality benchmark.
You do not have to choose permanently. Name one as your first choice and let Final Router fall back to the other when a provider fails - the request still gets answered, and the log shows which model replied.
Common questions
- Is GPT-5.1 or GPT-5 mini cheaper?
- GPT-5 mini is cheaper on input tokens - $0.25 vs $1.25 per 1M. Neither is marked up: Final Router bills provider list price.
- Can I switch between GPT-5.1 and GPT-5 mini without changing my code?
- Yes. Both are called through the same OpenAI-compatible endpoint - change only the model id ("openai/gpt-5.1" or "openai/gpt-5-mini"), or let a routing policy fall back from one to the other automatically.