Prerequisites
Get your Merchant ID
Log in to your and navigate to . Copy your Merchant ID.Fivo Dashboard and navigate to Integration.
Your Merchant ID looks like this:
fivo_live_969c4442-5741-4624-8305-427391683190Add the widget to your site
Add the following script tag to your HTML. Replace with your actual Merchant ID.YOUR_MERCHANT_ID
<!-- Fivo Payment Widget -->
<script async src="https://checkout.fivo.finance/v1/fivo.js"></script>
<fivo-button
merchant-id="YOUR_MERCHANT_ID"
amount="29.99"
currency="USDC">
</fivo-button>Fixed vs Variable Amount
amount. Widget Integration.Testnet and mainnet are separate environments
Test a payment
Choose the testing path that fits your stage:
Path A: Testnet (recommended first)
Use your fivo_test_ merchant ID and free testnet USDC from the Circle Faucet to validate your integration end-to-end with no real funds.
Get free test USDC from the Circle Faucet at faucet.circle.com.
Use your testnet merchant ID (fivo_test_...) in the widget code.
Make a test payment. It works exactly like production but with simulated tokens.
Path B: Mainnet smoke test
Once your integration is validated on testnet, test a real payment with a minimal amount.
Go to Integration in your dashboard and click "Try it live". It opens a real checkout pre-set to $0.01.
Connect your wallet and select a chain where you have USDC or EURC.
Confirm the $0.01 transaction. Real funds will be transferred.
View in dashboard
After the payment completes, you'll see it in your page. You'll also receive an email confirmation.Transactions
Once the payment is confirmed on-chain, it will appear in your page with the customer's email. Both you and the customer receive an email with the transaction details. Your customers can now pay you in USDC and EURC from any supported blockchain.Transactions
Examples
Fixed amount: Product or service
The customer pays an exact amount. Ideal for products, subscriptions, or invoices.
<script async src="https://checkout.fivo.finance/v1/fivo.js"></script>
<fivo-button
merchant-id="YOUR_MERCHANT_ID"
amount="29.99"
currency="USDC">
</fivo-button>This renders a "Pay $29.99 with USDC" button on your page (or EURC if you set currency="EURC"). When clicked, the Fivo checkout opens where the customer connects their wallet, sees their balance on each chain, selects a network, and confirms the payment.
Variable amount: Donation or tip
The customer chooses how much to pay. Just remove the amount attribute.
<script async src="https://checkout.fivo.finance/v1/fivo.js"></script>
<fivo-button
merchant-id="YOUR_MERCHANT_ID"
currency="USDC">
</fivo-button>This renders a "Pay with USDC" button (or "Pay with EURC" depending on your configured currency). When clicked, the checkout opens and the customer types the amount they want to pay before selecting a network and confirming.
Currency options