Billing and receipts
You pay for each request from prepaid credit, and every charge is settled against a signed receipt.
Reserve, then settle
- Before dispatch, the request’s worst-case cost is computed from the model’s public price and held from your available credit. If it does not fit, the request is refused with a 402 and nothing is spent.
- After completion, the actual cost is taken from the provider’s signed receipt, charged, and the rest of the hold released. The charge can never exceed the hold.
- Every response carries its cost in USD, and the usage page itemises every charge with sub-cent precision.
Signed receipts
Providers are paid against Ed25519-signed receipts recording exactly which units of work were done. Your charge is computed from the same receipt, never from self-reported token counts, so what you pay and what the provider was paid for are the same measured facts. The receipt’s identity is included in each response under openmayhem.receipt.
Prices
Prices are per model and public on the catalog. Price versions are immutable: each request records the version it was admitted under and settles at that price even if the price changes mid-flight. Every model’s page shows its full price history.
Media estimates and credit holds
An example image price illustrates the displayed settings. A representative tariff price is a standardized pricing reference, not a quote for every generation. Compare prices with the same dimensions, steps and output count.
Studio’s estimated_cost is the expected charge for the prepared request. maximum_cost is the temporary credit reservation, which can be higher. The final job cost is settled from receipted work; unused reserved credit is released. An estimate is not a guarantee of the final charge.
Price filters and representative-price ceilings use the tariff reference, even when a card shows an example image price. X-OpenMayhem-Max-Cost-Usd instead caps the worst-case retail hold for an individual request. Budget for the hold, not just the estimate.
How media settings affect cost
Read the selected model’s pricing units and granularity. Media may be priced per image, step, second or a resolution-dependent unit; smaller dimensions do not always lower the price.
For image workflows billed in whole megapixel-steps, usage is ceil(width Ă— height / 1,000,000) Ă— steps Ă— image count. A 960 Ă— 960 image uses one rounded megapixel per step; 1024 Ă— 1024 uses two. At the same rate, steps and count, the resolution-dependent usage doubles. This formula is not universal for video or other tariffs.
The applicable rate and its granularity convert usage into cost; fees or minimum charges may also apply. Recheck the quote after changing settings or routing, and use the settled job cost for your actual spend.
Credit
- Top up by card on the credit page; credit is denominated in USD and never expires.
- Refunded purchases claw back exactly the credited amount. A payment dispute freezes the account while it is open; a dispute resolved in your favour restores the credit.
Retail cost versus wholesale routing price
X-OpenMayhem-Max-Cost-Usd limits the customer's worst-case retail hold. The stricter of this value and the API key's per-request cap wins. It is an exact decimal USD string.