GPT-5 mini → GPT-5.6 Luna: cost per request on six tasks
GPT-5.6 Luna costs 22–38% less than GPT-5 mini per request on six common tasks. It costs no more per result that works if its results work first time at least 63% as often as GPT-5 mini's on translation, and 79% as often on search re-ranking. OpenAI has announced GPT-5 mini's API shutdown for 2026-12-11.
List prices per million tokens
| Model | Input | Cached input | Output |
|---|---|---|---|
| GPT-5 mini | $0.25 | $0.025 | $2.00 |
| GPT-5.6 Luna | $0.20 | $0.02 | $1.20 |
Prices checked 2026-11-12.
Cost per 1,000 requests
| Task | GPT-5 mini | GPT-5.6 Luna | Change | Cheaper per result that works if it works first time at least |
|---|---|---|---|---|
| Support bot answerInstructions, three help-centre passages and the customer's question in; a short answer out. | $1.35 | $0.96 | 29% less | 72% as often as GPT-5 mini |
| Invoice field extractionInstructions and one invoice's text in; about 15 fields as JSON out. | $1.13 | $0.80 | 29% less | 72% as often as GPT-5 mini |
| Lead scoringScoring rules and one lead's form answers in; a score and a one-line reason out. | $0.50 | $0.36 | 28% less | 72% as often as GPT-5 mini |
| Email reply draftInstructions and the email thread so far in; a reply of about 300 words out. | $1.18 | $0.78 | 34% less | 67% as often as GPT-5 mini |
| TranslationInstructions and about 500 words of text in; the same text in another language out. | $1.83 | $1.14 | 38% less | 63% as often as GPT-5 mini |
| Search re-rankingA search query and 20 result snippets in; the ids of the best five, in order, out. | $1.10 | $0.86 | 22% less | 79% as often as GPT-5 mini |
Token counts are typical sizes, not measurements.
GPT-5 mini is being shut down
OpenAI has announced GPT-5 mini's API shutdown for 2026-12-11, with gpt-5.6-terra as the replacement (source).
Test it on your own prompt
The model switch test runs your prompt on both models side by side with your own API key, in your browser.