GPT-5.1 vs GPT-5 nano
Benchmarks, API pricing and specs, head to head. Data updated 2026-06-10.
GPT-5.1
59.6OpenAI · Nov 2025
A November 2025 update to GPT-5 with adaptive reasoning that spends thinking tokens only when a task needs them.
GPT-5 nano
OpenAI · Aug 2025
OpenAI's cheapest model — $0.05 per million input tokens — for latency-critical routing, autocomplete and bulk tagging.
The verdict
These two models don't yet share verified results on the benchmarks we track, so judge them on specs, pricing and intended use. On price the gap is dramatic: GPT-5 nano works out roughly 25x cheaper per blended million tokens.
Specs & pricing
| GPT-5.1 | GPT-5 nano | |
|---|---|---|
| modhub Index | 59.6 | — |
| Input price / 1M | $1.25 | $0.05 |
| Output price / 1M | $10 | $0.4 |
| Context window | 400K | 400K |
| Max output | 128K | 128K |
| Open weights | no | no |
| Reasoning model | yes | yes |
| Multimodal input | text, image | text, image |
| Knowledge cutoff | Sep 2024 | May 2024 |
| Released | Nov 2025 | Aug 2025 |
| Example monthly cost* | $27.50 | $1.10 |
* 10M input + 1.5M output tokens per month at list prices, no caching. Green = better value on that row.
Frequently asked questions
- Which is better, GPT-5.1 or GPT-5 nano?
- These two models don't yet share verified results on the benchmarks we track, so judge them on specs, pricing and intended use. On price the gap is dramatic: GPT-5 nano works out roughly 25x cheaper per blended million tokens.
- Which is cheaper, GPT-5.1 or GPT-5 nano?
- GPT-5.1 costs $1.25/$10 per million input/output tokens, while GPT-5 nano costs $0.05/$0.4. For a typical workload of 10M input and 1.5M output tokens per month, that's $27.50 versus $1.10.
- Which model is better for coding, GPT-5.1 or GPT-5 nano?
- We don't yet track SWE-bench Verified results for both models; check their individual pages for coding-related scores.