Cover fee calculation in REST API

The REST API now includes a GET /v1/donations/fee endpoint that calculates processing fees before a donation is created. Pass the donation amount and currency — the endpoint returns the fee and the total with the fee included.

Those numbers can be shown to the supporter before checkout. If they agree to cover the fee, fee_amount is passed alongside the donation amount in the POST request.

The endpoint uses the same fee calculation logic as checkout, so no custom math is needed on the integration side.

For more information, see the REST API docs →