GPT-5.1-Codex-Mini vs gpt-oss-20b: pricing comparison
gpt-oss-20b is the cheaper option at $0.02/$0.09 per 1M input/output tokens — GPT-5.1-Codex-Mini ($0.25/$2) costs about 14x more per input token. Full spec-by-spec breakdown below.
| GPT-5.1-Codex-Mini | gpt-oss-20b | |
|---|---|---|
| Input /1M tokens | $0.25 | $0.02 |
| Output /1M tokens | $2 | $0.09 |
| Cache read /1M | $0.03 | $0.01 |
| Context window | 400K | 131K |
| Provider | OpenAI | OpenAI |
| Vision input | Yes | No |
| Released | Nov 2025 | Aug 2025 |
Real workload costs: GPT-5.1-Codex-Mini vs gpt-oss-20b
Cost per single request at common token profiles — the cheapest model for each workload is highlighted.
| Workload | Tokens (in / out) | GPT-5.1-Codex-Mini | gpt-oss-20b |
|---|---|---|---|
| Chatbot message | 500 / 300 | $0.0007 | <$0.0001 |
| RAG query with context | 4,000 / 500 | $0.0020 | $0.0001 |
| Document summarization | 20,000 / 1,000 | $0.0070 | $0.0004 |
| Agent coding session | 100,000 / 5,000 | $0.04 | $0.0022 |
Frequently asked questions
Which is cheaper: GPT-5.1-Codex-Mini vs gpt-oss-20b?
gpt-oss-20b is the cheapest on input tokens at $0.02 per 1M, and gpt-oss-20b is cheapest on output at $0.09 per 1M. GPT-5.1-Codex-Mini costs about 14x more per input token than gpt-oss-20b.
How much does GPT-5.1-Codex-Mini cost per 1M tokens?
GPT-5.1-Codex-Mini costs $0.25 per 1M input tokens and $2 per 1M output tokens on the OpenAI API, with a 400K-token context window.
How much does gpt-oss-20b cost per 1M tokens?
gpt-oss-20b costs $0.02 per 1M input tokens and $0.09 per 1M output tokens on the OpenAI API, with a 131K-token context window.
What does a typical request cost on GPT-5.1-Codex-Mini vs gpt-oss-20b?
For a typical request with 2,000 input and 500 output tokens: GPT-5.1-Codex-Mini costs $0.0015, gpt-oss-20b costs <$0.0001. At 1,000 requests/day for a month that is $45.00 for GPT-5.1-Codex-Mini vs $2.43 for gpt-oss-20b.
Estimate your own workload with the per-model calculators (GPT-5.1-Codex-Mini, gpt-oss-20b), browse all current prices on the live model pricing dashboard, or run these models head-to-head on a real prompt (free account required). Prices may differ from provider list prices for batch or tiered usage.
Pricing data via the OpenRouter models API.