OpenAI o4-mini is cheaper than GPT-5 Pro at $1.1/M vs $15/M input tokens.
| Spec | GPT-5 Pro | OpenAI o4-mini |
|---|---|---|
| Input price | $15/M tokens | $1.1/M tokens |
| Output price | $120/M tokens | $4.4/M tokens |
| Context window | 400K tokens | — |
| Weights | Closed | Closed |
| Free API (OpenRouter) | No | No |
| Released | Oct 2025 | Apr 2025 |
| SWE-bench Verified | 74.9% | 68.1% |
Not enough votes to call it. On the specs, GPT-5 Pro has the edge: bigger model tier, newer, bigger context window.
OpenAI o4-mini costs 27x less per token.
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OpenAI o4-mini is cheaper on both: 14× input, 27× output.
Per million tokens. Prices and uptime via OpenRouter, checked 11 Sep 2026.
OpenAI o4-mini uses 4.6x more transitions