GNU Taler is a payment system that offers privacy-preserving payments for buyers while ensuring income-transparency for sellers. Our payment system does not use a blockchain and can process tens of thousands of payments on a single computer with negligible costs per transaction. Modern cryptography is used to implement digital cash held decentralized in self-custody.

Because spending digital cash does not require authentication, GNU Taler offers superior usability compared to other payment solutions. Building on ideas from Oral Information Management (OIM), we created a version of the Taler wallet that does not require users to be able to read, and have conducted usability studies with illiterate and innumerate people that were quickly able to correctly use the GNU Taler wallet for payments despite being unable to read 2-digit numbers.

As Free/Libre Open Source software we are able to develop the solution in collaboration with a growing group of academics, volunteers, non-profits and small businesses. This allows our small team to drive an outsized number of innovations in a field where proprietary systems have long stifled innovation. As a result, secure payments to offline merchants, programmable money, business contracts using secure multiparty computation, subscriptions, coupons, privacy-preserving tax deductable donations and even post-quantum cryptography are other present or upcoming features.

The payment system is operational today in Swizerland (eCHF), and is expected to be operated by GLS for Euros starting in Q3'2025.