Cashu is a lightweight, privacy‑preserving ecash system that runs on top of the Lightning Network and settles on‑chain. It uses zero‑knowledge proofs to hide the value of a transfer while remaining fully traceable when required.
Cashu is an ecash protocol that allows you to mint, transfer, and spend Bitcoin value without revealing the amount or the sender/receiver in public transactions. It leverages the Lightning Network for instant settlement while maintaining on‑chain traceability for regulatory compliance. Think of it as a privacy‑preserving UTXO that can be moved anywhere on the Lightning network.
At the core of Cashu is a zero‑knowledge range proof that proves the value of a note without exposing it. This means you can pay for goods or services with a Cashu note and the recipient can verify that the note contains sufficient value, while the transaction remains private on‑chain.
Cashu uses a set of “notes” minted by a mint and signed with a unique key. Each note contains an amount and a unique identifier that the mint keeps encrypted. Transfers are executed with the Lightning Network, but minting and redeeming are done via on‑chain transactions that are fully verifiable.
Several wallet applications support Cashu, from the Cashu Web Wallet to Melt’s Lightning Wallet. Below are quick links to some popular ones:
To begin using Cashu, you’ll need a Lightning‑ready wallet that supports the protocol. Most of the wallets listed above have a Cashu switch or integration. Once installed, create a new Cashu account, mint a few notes, and start experimenting.