In a nutshell
Blockradar Checkout lets you accept stablecoin payments via shareable links—no customer accounts or complex integrations required. Create a link, share it, and receive payments directly to your wallet.
Blockradar Checkout lets you accept stablecoin payments via shareable links—no customer accounts or complex integrations required. Create a link, share it, and receive payments directly to your wallet.
Prerequisites
Before creating payment links, ensure you have:1
API Key
Get your API key from the Blockradar Dashboard. Navigate to Developers to generate one.
2
Master Wallet Created
Create a master wallet in the dashboard (see Create a Master Wallet). Payment links are tied to a wallet.
3
Checkout Plan Active
Ensure the Checkout feature is enabled on your account. Contact [email protected] if you need to activate it.
4
Webhook Configured (Optional)
Set up webhooks to receive real-time payment notifications. See Webhooks for setup details.
Introduction
Payment links are shareable URLs that allow anyone to send stablecoin payments to your wallet. They’re perfect for:- E-commerce: Send to customers for product purchases
- Invoicing: Include in invoices for services rendered
- Donations: Share on social media or websites
- Marketplace payments: Facilitate peer-to-peer transactions
- Subscription billing: Recurring payment collection
How Payment Links Work
Creation
Create a payment link with specific parameters like amount, name,
description, and payment limits.
Sharing
Share the generated URL with your customers through email, messaging, or
embed it on your website.
Payment
Customers click the link, enter their payment details, and complete the
transaction.
Confirmation
You receive webhook notifications and can track payment status in real-time.
Payment Link Features
- Customizable Parameters: Set amount, description, payment limits, and metadata
- Shareable URLs: Generate unique payment links for each transaction
- Customer Pre-filling: Pre-populate customer details via URL query parameters
- Real-time Tracking: Monitor payment status and receive webhook notifications
- Multi-network Support: Accept payments across different blockchain networks
- Auto-sweep Integration: Funds automatically consolidated to master wallet
Multi-Asset Support
- USDT, USDC, DAI, BUSD across multiple blockchains
- Ethereum, BSC, Polygon, Base, Arbitrum, Optimism, Tron, Solana, Celo
- Automatic conversion and routing for optimal user experience
Flexible Configuration
- Fixed amounts for specific products/services
- Variable amounts for donations or custom payments
- Payment limits to ensure timely payments
- Custom metadata for tracking and analytics
- Webhook notifications for real-time updates
Security & Compliance
- AML screening on all incoming payments
- Address validation and verification
- Fraud detection and prevention
- Regulatory compliance across jurisdictions
Payment Flow
1. Payment Link Creation
When you create a payment link, Blockradar returns a unique payment URL:2. Customer Pre-filling with Query Parameters
You can enhance the payment URL with query parameters to automatically pre-fill customer details on the payment page:name- Customer’s name (appears on payment page)email- Customer’s email addressreference- Custom reference that will be included in transaction responsesamount- Amount shown to the customer on the payment page. It is display-only: Blockradar does not store it or check the payment against it (see When the Amount Received Differs)redirectUrl- URL to redirect to after payment completion
3. Post-Payment Redirect
When aredirectUrl is provided, customers will be automatically redirected to your specified URL after payment processing is complete. The redirect URL will include the following query parameters:
Redirect Query Parameters:
status- Payment status (success,failed,pending)tx_reference- Transaction reference IDreference- Your custom reference (if provided)slug- Payment link identifier
The redirect only occurs after payment processing is complete. If no
redirectUrl is provided, customers will see the default payment completion
page.4. Amount Configuration
Payment links support two amount modes: Fixed Amount (Pre-set)- When you specify an
amountduring creation, customers cannot modify the payment amount - Ideal for specific products or services with set pricing
- Example: Product purchase for exactly $99.99
- When no
amountis specified, customers can enter their own payment amount - Perfect for donations, tips, or flexible pricing scenarios
- Customers see an amount input field on the payment page
amount sets the amount Blockradar expects. The amount query parameter changes what the payment page shows, not what Blockradar checks.
5. Payment Processing
Customers visit the payment link, review pre-filled details, and complete the transaction using their preferred stablecoin.6. Transaction Response
Thereference parameter from the URL will be included in the transaction response and webhook payloads, allowing you to link payments back to your internal systems.
When the Amount Received Differs
Customers send stablecoins from their own wallet or exchange, so the amount that arrives can differ from the amount on the payment page. They may type a different number, or an exchange may deduct its withdrawal fee from the amount sent. How Blockradar records the payment depends on whether the link has a fixed amount.
In every payload,
amountPaid is what the customer has actually sent. On a fixed-amount link, amount is the link’s amount converted to the token paid and rounded down to that token’s decimals, so an overpayment of 100.50 arrives with amount: "100" and amountPaid: "100.5". On a no-amount link, amount and amountPaid are both what was received.
Underpaid Fixed-Amount Links
A payment below the link’s amount is markedINCOMPLETE and sends a deposit.incomplete webhook. Any shortfall counts, even a fraction of a cent. The payload has the same fields as deposit.success, with the total received so far in amountPaid and two extra keys in metadata:
remainingAmount: how much is still duepartialPayments: one entry per on-chain payment received, with itshash,amountandsenderAddress
metadata also keeps any metadata you set on the payment link.
If the customer sends the rest to the same payment address while it is still active, Blockradar adds it to amountPaid. A payment that still leaves the total short sends another deposit.incomplete. The payment that reaches the link’s amount makes the transaction SUCCESS and sends deposit.success with the cumulative amountPaid. Every event carries the same transaction id.
Don’t wait for a deposit.incomplete before every deposit.success. If the final payment arrives while an earlier deposit.incomplete is still being retried, that delivery is dropped and only deposit.success is sent.
To review underpaid payments, list a link’s transactions with status=INCOMPLETE (see Fetching Payment Link Transactions) and compare amount with amountPaid.
Charging a Different Amount per Customer
If the amount varies per order, create a payment link without anamount and pass each order’s amount and reference in the URL:
99.99 on the payment page. Whatever they send, the payment completes and you receive deposit.success with that reference. Compare amountPaid with the order total on your side, and decide there how to handle a shortfall or an excess.
Try It Out
Experience Blockradar payment links firsthand with our live demo: 🔗 Demo Payment Link: https://pay.blockradar.co/demo This demo showcases:- Payment Flow: Complete customer experience from link to completion
- UI/UX: Modern, intuitive payment interface
- Stablecoin Options: Multiple payment methods and networks
- Real-time Updates: Live transaction status and confirmations
The demo payment link is for testing purposes only. No real transactions will
be processed.
Creating Payment Links
Basic Payment Link
Create a simple payment link for a fixed amount:Variable Amount Payment Link
Allow customers to choose their payment amount:Payment Link with File Upload
Include a file (e.g., invoice, product image) with your payment link using form-data: Form Data Fields:name: Service Invoicedescription: Web development services - January 2024amount: 1500.00redirectUrl: https://company.example.com/payment-successsuccessMessage: Payment received! We’ll start working on your project.metadata: invoice_id: INV-2024-001, service: web_developmentfile: [cover.png] (file upload)
When including file uploads, use form-data instead of JSON. The file will be
stored and accessible via the payment link.
Payment Link Parameters
Required Parameters
Optional Parameters
Payment Flow
Customer Experience
-
Click Payment Link
- Customer receives and clicks the payment link
- Link opens to a secure payment page
-
Select Payment Method
- Choose from available stablecoins
- Select preferred blockchain network
- Enter payment amount (if variable)
-
Complete Payment
- Customer confirms transaction details
- Payment is processed on the blockchain
- Real-time confirmation and status updates
-
Success Confirmation
- Payment confirmation page
- Optional redirect to your website
- Receipt and transaction details
Merchant Experience
-
Real-time Notifications
- Webhook events for payment status
- Email notifications (if configured)
- Dashboard updates
-
Payment Tracking
- Transaction history and status
- Payment analytics and reporting
- Integration with your systems
Address Lifecycle
Webhook Events
Payment links trigger the following webhook events when payments are received:Webhook Payload Example
Key Webhook Data Fields
The webhook payload includes comprehensive information about the payment:The
reference field in webhook payloads corresponds to the reference query
parameter you include in the payment URL. This allows you to track payments
back to specific orders, customers, or internal references in your system.Best Practices
Security
- Use HTTPS for all payment link sharing
- Monitor webhook events for suspicious activity
- Implement rate limiting on your webhook endpoints
User Experience
- Clear descriptions of what the payment is for
- Mobile-optimized payment pages
- Multiple payment options when possible
Integration
- Store payment link IDs for tracking
- Use metadata to link payments to your systems
- Implement webhook retry logic for reliability
- Test webhooks in sandbox environment first
Use Cases & Examples
E-commerce Store
Service Invoice
Donation Campaign
Subscription Service
These examples use the correct Blockradar payment links API parameters. The
metadata field must be sent as a JSON string in form-data, and file
uploads are supported for additional content.Testing & Development
Sandbox Environment
- Use testnet networks for development
- Test webhook delivery and handling
- Verify payment flows end-to-end
- Test edge cases and error scenarios
Webhook Testing
- Use tools like webhook.site for testing
- Verify signature validation
- Test retry mechanisms
- Monitor webhook delivery rates
Checkout Plan
Blockradar Checkout is a programmable stablecoin payment layer for accepting onchain payments via links, embedded QR codes, and WalletConnect. Funds settle directly to your non-custodial wallets with built-in support for swap, bridge, and treasury routing.Pricing
0.75% per transaction
Simple, transparent pricing with no monthly subscription costs.
Supported Stablecoins
- USDC, USDT, cNGN, IDRX, EUROC, and more
Multi-Chain Support
- Ethereum, Polygon, Base, Solana, Tron, Celo, and more
Treasury Management
- Swap and Bridge: Convert and move assets across chains
- Auto-settlement: Automatically settle to your preferred currency
- Circle Gateway: Access Circle’s cross-chain transfer protocol
- Auto-sweeping: Consolidate funds to your master wallet
This plan does not include Wallet-as-a-Service (WaaS) features or the
provisioning of dedicated wallets for your end users.
Fetching Payment Link Transactions
You can retrieve all transactions associated with a specific payment link using the dedicated transactions endpoint. This is useful for:- Payment Tracking: Monitor all payments received through a specific link
- Reconciliation: Match payments to orders or invoices
- Reporting: Generate reports for specific payment links
Query Parameters
Example Response
Support & Resources
API Reference
- Create Payment Link
- Get All Payment Links
- Get Payment Link
- Update Payment Link
- Get Payment Link Transactions
Getting Help
- Email: [email protected]
- API Reference: Checkout
Checkout and payment links are a powerful way to accept stablecoin payments with minimal
integration effort. Start with simple use cases and gradually add complexity
as you become more familiar with the system.

