Quick Start

Ⅰ. Bridge BTC to Mint $zkBTC in 4 Steps

Follow 4 simple steps to bridge BTC using a wallet that supports the OP_RETURN feature:

1. ✅ Enter zkBTC Bridge operator recipient address

bc1qcwc08898aseahq2e5920m9395py3jjtm2xnt0s90slqra7cry2dq2xv9uq

1. Specify the amount to send Enter the amount of BTC you want to bridge. No less than 21,000 sats ( ⚠️ ≥ 0.00021 BTC )

1. Add your Ethereum address without "0x" prefix in the OP_RETURN field Open the Advanced Settings in your wallet. Find the OP_RETURN field and enter your Ethereum address without "0x" prefix for receiving $zkBTC.

1. Confirm and send the transaction After it's confirmed on the Bitcoin network, your $zkBTC will be minted and sent to the Ethereum address you provided in OP_RETURN

---

Ⅱ. What's OP_RETURN?

OP_RETURN is a script opcode used to mark a transaction output as unspendable, and can be used to carry additional data for a transaction.

OP_RETURN applications in zkBTC Bridge？

It's used to specify the ETH receiving address so that the smart contract knows where to send the minted $zkBTC tokens.