Cashu is Ecash for Bitcoin

Cashu is a free and open-source Chaumian ecash system built for Bitcoin. Cashu offers near-perfect privacy for users of custodial Bitcoin applications. Nobody needs to knows who you are, how much funds you have, and with whom you transact.

What is Cashu?

Cashu is a new ecash protocol for custodial Bitcoin applications that is tightly integrated into the Lightning network. An Ecash system consists of two parts, the mint and the Ecash wallet. Ecash transactions between users are untraceable and instant. A Cashu mint does not know who you are, what your balance is, or who you're transacting with. Users of a mint can exchange ecash privately without anyone being able to know who the involved parties are. Bitcoin payments are executed without anyone able to censor specific users.


Open-source Ecash

Cashu is a free and open-source protocol. Anyone can run a mint.

Bearer token

Ecash transactions are instant and final, just like physical cash.


Blind signatures preserve user privacy. Transactions are peer-to-peer.


Cashu tokens support spending conditions like P2PK and HTLCs.

Ecash for the web

Ecash payments can be included in web requests.

Range of application

Use Cashu for your website. Or a whole bank.

Explore Cashu


Cashu is an Ecash implementation based on David Wagner's variant of Chaumian blinding.


Cashu NUTs (Notation, Usage, and Terminology) are Cashu's protocol specifications and the developer libraries make it easy to write wallets and mints.


There are many apps that implement the Cashu protocol. Apps are available as mobile apps for iOS and Android, progressive web apps (PWA), and command-line tools (CLI).


Cashu libraries are available for various programming languages. Click here to see the full list. Here are some examples.


Learn about Cashu

Articles and Podcast about Cashu and Chaumian ecash.

Read more

Explore Projects

Explore the different Open Source Cashu apps that have been built so far.

Read more

Cashu Protocol

Go deeper into how the Cashu protocol works.

Read more

Join Cashu R&D

We have a Discord server and a Telegram channel focussed on Cashu R&D. If you're developer, please join us!