GPT-5 nano vs gpt-oss-20b
Benchmarks, API pricing and specs, head to head. Data updated 2026-06-10.
OpenAI · Aug 2025
OpenAI's cheapest model — $0.05 per million input tokens — for latency-critical routing, autocomplete and bulk tagging.
OpenAI · Aug 2025
The small gpt-oss variant that runs on a 16GB consumer GPU or laptop — local reasoning for everyone, Apache 2.0 licensed.
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. gpt-oss-20b is about 1.6x cheaper per blended million tokens (3:1 input:output mix). GPT-5 nano also takes 400K of context versus 131K for gpt-oss-20b. And gpt-oss-20b is open-weights (Apache 2.0), so it can be self-hosted — a structural advantage if data control or vendor independence matters.
Specs & pricing
| GPT-5 nano | gpt-oss-20b | |
|---|---|---|
| modhub Index | — | — |
| Input price / 1M | $0.05 | $0.05 |
| Output price / 1M | $0.4 | $0.2 |
| Context window | 400K | 131K |
| Max output | 128K | 131K |
| Open weights | no | yes (Apache 2.0) |
| Reasoning model | yes | yes |
| Multimodal input | text, image | text |
| Knowledge cutoff | May 2024 | Jun 2024 |
| Released | Aug 2025 | Aug 2025 |
| Example monthly cost* | $1.10 | $0.8 |
* 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 nano or gpt-oss-20b?
- These two models don't yet share verified results on the benchmarks we track, so judge them on specs, pricing and intended use. gpt-oss-20b is about 1.6x cheaper per blended million tokens (3:1 input:output mix). GPT-5 nano also takes 400K of context versus 131K for gpt-oss-20b. And gpt-oss-20b is open-weights (Apache 2.0), so it can be self-hosted — a structural advantage if data control or vendor independence matters.
- Which is cheaper, GPT-5 nano or gpt-oss-20b?
- GPT-5 nano costs $0.05/$0.4 per million input/output tokens, while gpt-oss-20b costs $0.05/$0.2. For a typical workload of 10M input and 1.5M output tokens per month, that's $1.10 versus $0.8.
- Which model is better for coding, GPT-5 nano or gpt-oss-20b?
- We don't yet track SWE-bench Verified results for both models; check their individual pages for coding-related scores.