Published 2026-10-12 · 5 min read
What is EIP-681?
EIP-681 is an open standard for crypto payment requests. It defines a URL format — ethereum: — that wallets understand. When a user clicks it, their wallet opens with the recipient, amount, and token already filled in. Think of it as the crypto equivalent of a payment button.
The format
For a native coin (ETH) payment:
ethereum:0xRecipient@ChainId?value=1000000000000000000
value is in wei (1 ETH = 10^18 wei). For an ERC-20 token like USDC you call its transfer function:
ethereum:0xUSDC_Contract@ChainId?function=transfer(address,uint256)(0xRecipient,AmountInBaseUnits)
Chain IDs you'll use
| Chain | Chain ID | USDC contract |
|---|---|---|
| Ethereum | 1 | 0xA0b8...eB48 |
| Base | 8453 | 0x8335...2913 |
| Arbitrum | 42161 | 0xaf88...e5831 |
| Polygon | 137 | 0x3c49...3359 |
| BNB Chain | 56 | 0x8AC7...d580d |
Why this matters for creators
A payment link removes the #1 cause of failed crypto payments: manual address entry. The CryptoCheckout Kit generates these links for you across six chains and verifies payment before releasing a download.
Generate payment links without code.
Get the CryptoCheckout Kit →