Payment acceptance — crypto and cards
At checkout your buyer picks any coin and network — bitcoin, ether, USDT, USDC — or pays with an ordinary card. You are credited in the currency you chose. The payment link goes on your site without a single line of code; the API is only needed when the amount comes from a cart.
1.5% per payment. Your dashboard opens right away; accepting payments starts after review.
settled — ship the order01 / Getting connected
A button with a link covers most cases. The API is for when the price is calculated on your side.
No code
Create it in the dashboard, copy the link, put it on your site as a button. The price is either fixed or entered by the buyer.
A price tag can be reusable — for a catalogue item, or single-use — for one person's invoice. A single-use tag closes the moment the first buyer proceeds to pay: two people who opened the link at once won't pay twice for one item.
<a href="https://api.priem.io/pay/YOUR-PRICE-TAG">
Pay with crypto
</a>When the amount comes from a cart
Your server creates a payment for the amount it needs and sends the buyer to the link it gets back. The project is identified by the key, so there is no need to name it in the body.
POST https://api.priem.io/v1/payments
Authorization: Bearer priem_…
{
"amount": "49.00",
"currency": "USD",
"idempotencyKey": "order-12345"
}Take the idempotency key from your order number, not from the clock and not at random. A repeated request with the same key returns the same payment instead of issuing a second invoice. A key built from Date.now() protects against nothing.
Card payment works at the same checkout and needs no setup from you. The buyer buys bitcoin from the provider, it lands straight on the invoice address, and the payment goes through like any other.
The card minimum is 10 dollars. Below that the button isn't shown at all, and the buyer is told why.
02 / Money
There are three fees and only one of them is ours. The network takes the other two, and we show them here rather than after you've signed up.
To us, per payment
1.5%
Withheld on crediting and shown in the callback as its own field.
To the network, on payout
~1 USDT
Flat on TRON, paid by you. Accumulating and withdrawing at once is cheaper than per payment.
To the network, on payment
Paid by the buyer
On top of your price. It doesn't scale with the amount, so on a small order it shows.
| Paying with | $5 order | $30 order | $100 order |
|---|---|---|---|
| USDT on BSC | +1.3% | +0.5% | +0.3% |
| USDT on TON | +9.3% | +1.8% | +0.8% |
| USDT on TRON | +16.3% | +3.0% | +1.1% |
| USDT on Ethereum | +19.5% | +3.5% | +1.3% |
Caveat Selling for under 10 dollars through crypto is hard. On a three-dollar order even a cheap network eats a visible share, and TRON or Ethereum add a quarter of the price. If your plans are small, sell them in bundles. We say this before you connect, not after the first abandoned orders.
03 / Developers
Create a payment, wait for the callback, verify the signature, ship on settled. Nothing else is required.
// raw body, before parsing JSON:
// the signature is computed over bytes
const expected = createHmac('sha256', secret)
.update(`${timestamp}.${rawBody}`)
.digest('hex');
if (!timingSafeEqual(a, b)) return res.sendStatus(401);
markOrderPaid(event.paymentId, event.creditedAmount);
res.sendStatus(200);{timestamp}.{body}, headers X-Priem-Timestamp and X-Priem-Signature.GET /v1/payments/{id} always returns the current state. Don't rely on the callback alone.Payment states
createdCreated, no coin chosen yetawaiting_paymentCoin chosen, awaiting transferonramp_pendingPaying by card, buying cryptodetectedTransfer visible on the networkconfirmingConfirmations accumulatingconvertingExchanging into your currencysettledMoney is on your balanceunderpaidLess than required arrivedexpiredThe invoice ran out of timerefundedReturned to the buyerShip the order on settled and on nothing else.
04 / Reliability
The work you never see from the dashboard, and whose absence is what loses money.
Every night we square everything we owe merchants against what actually sits with the provider. A shortfall stops payouts automatically — until it's explained, not until morning.
A new wallet address becomes usable a day after it is added. It is the only thing standing between a hijacked dashboard and an empty balance. It's inconvenient exactly once.
The rate moved, the wallet kept its cut — slightly less arrived. Within tolerance (1% by default) the payment still closes and you receive the full price of the tag. We cover the difference.
Logins, keys, addresses, payouts and price tags are written to a log ordered by a running number. Five failed login attempts lock the account for fifteen minutes.
05 / Before you decide
Registration takes a minute, setup about half an hour, and nearly all of that goes into the callback handler.