Relayers in Tornado Cash
Relayers in Tornado Cash Official enable gasless withdrawals, enhancing privacy by allowing users to withdraw funds without exposing their wallet’s balance. This page explains how relayers work and how to use them.
What is a Relayer?
A relayer is a third-party service that submits withdrawal transactions on behalf of users. By covering gas fees, relayers allow users to withdraw funds from Tornado Cash Official pools without needing ETH in their withdrawal wallet, reducing traceability.
Note: Relayers charge a small fee, typically a percentage of the withdrawn amount, to cover gas costs.
How Relayers Work
Relayers integrate with Tornado Cash Official’s smart contracts to process withdrawals:
- User Initiates Withdrawal: The user provides their private note and withdrawal address to the relayer via the Tornado Cash Official interface.
- Relayer Submits Transaction: The relayer constructs and submits the withdrawal transaction, including the zk-SNARK proof, to the blockchain.
- Fee Deduction: The relayer deducts a fee from the withdrawn amount and sends the remainder to the user’s address.
- Completion: The user receives funds without using their own wallet for gas, preserving anonymity.
Benefits of Using Relayers
Relayers offer several advantages:
- Enhanced Privacy: No need to fund the withdrawal wallet with ETH, reducing on-chain links.
- Convenience: Gasless withdrawals simplify the process for users with empty wallets.
- Decentralization: Multiple relayers operate independently, ensuring no single point of failure.
Using a Relayer
Follow these steps to withdraw using a relayer:
- Access Tornado Cash Official: Connect to the official interface (verify the URL on GitHub).
- Select Relayer: Choose a relayer from the interface’s list, checking its fee and reputation.
- Enter Details: Provide your private note and withdrawal address.
- Confirm Withdrawal: Approve the transaction, and the relayer will process it.
- Verify Receipt: Ensure funds arrive at the specified address, minus the relayer’s fee.
Warning: Only use trusted relayers listed on the official Tornado Cash Official interface to avoid scams.
Running a Relayer
Users can run their own relayer to earn fees:
- Follow setup instructions on GitHub.
- Stake TORN tokens to register as a relayer (see staking).
- Maintain a node to process transactions and cover gas costs.
Risks and Considerations
Be aware of potential risks:
- Relayer Trust: Malicious relayers could log withdrawal details, though zk-SNARKs prevent linking deposits.
- Fees: High gas prices may increase relayer fees, reducing your withdrawal amount.
- Availability: Relayers may go offline, so check availability before withdrawing.
Learn more about risks and mitigation strategies.
Further Reading
Explore related topics:
- How Does Tornado Cash Work? for the core mechanism.
- zk-SNARKs for technical details.
- FAQ for common questions.