B-money, proposed by computer scientist Wei Dai in 1998, never became an operational digital currency. Even so, it left a clear imprint on crypto history. Its design described decentralized bookkeeping, money creation through computational work, and transaction authentication with public keys and digital signatures, ideas that later appeared in practical systems such as Bitcoin.
Dai’s proposal aimed at a form of digital cash that would not depend on governments or centralized institutions. In his model, participants interacted through digital pseudonyms, while transfers and contracts were handled through cryptographic mechanisms rather than outside enforcement. Dai wrote that it was not even theoretically clear at the time how such a community could function, since cooperation requires both a medium of exchange and a way to enforce contracts.
Two protocols, neither implemented
B-money was built around two theoretical protocols. In the first, every participant maintained a separate database showing how much money belonged to each pseudonym. New money was created by solving computational problems, and the amount issued matched the cost of the computing effort. To transfer funds, the sender broadcast a signed message instructing payment to another pseudonym. Contracts could also be defined, including maximum reparations for default and arbitration for disputes.
The second protocol assigned balance maintenance to a subset of participants called servers. Transactions were broadcast over a Usenet-style channel, and affected users checked whether a randomly selected subset of servers had processed them. Servers had to deposit funds that could be used for fines or rewards tied to misconduct, and they were required to periodically publish and commit to their money creation and ownership databases.
The article makes the limitation plain. Both versions were theoretical proposals, and neither became a working network.
Shared ideals with Bitcoin, different execution
B-money and Bitcoin were driven by similar goals, but they diverged sharply in execution. B-money was introduced by Wei Dai in 1998 and remained a proposal. Bitcoin emerged from Satoshi Nakamoto’s 2008 white paper and became the first practical decentralized cryptocurrency.
Their decentralization models also differ. B-money envisioned a system in which all transactions were verified by every participant, a fully distributed approach. Bitcoin relies on a decentralized network of nodes and reaches consensus through proof-of-work, without requiring each participant to validate every transfer. Monetary design is another split: B-money did not define a fixed supply cap, while Bitcoin limits issuance to 21 million coins and releases new coins to miners, with halvings taking place about every four years.
On privacy, B-money aimed for untraceable transfers using pseudonyms and cryptographic techniques. Bitcoin offers pseudonymous transactions recorded on a public blockchain, where identities are not directly attached to public keys. The adoption gap is just as clear: B-money stayed on paper, while Bitcoin achieved broad recognition and helped expand the wider cryptocurrency market.
Wei Dai’s own view of the connection
Dai later said he did not create Bitcoin and had only described a similar idea more than a decade earlier. He also said that, from his understanding, Satoshi Nakamoto had not read his article before independently arriving at the concept and only learned of it later, crediting him in the paper. For that reason, Dai described his connection to Bitcoin as quite limited.
That does not erase B-money’s place in the timeline. It never turned into a functioning currency, but it contributed core concepts that became central to later cryptocurrencies, especially decentralized ledgers, cryptographic verification, and the idea of digital cash operating without a central intermediary.