Wasabi Wallet White Paper
A Wasabi user can, at any time, opt to mix any of his coins (called “Unspent Transaction Outputs” or “UTXOs”).
Within an hour, his coins get mixed with up to one hundred other users’ coins in such a way that the recorded
blockchain transaction, which includes a large number of inputs and outputs, is virtually impossible to trace
through. Fees are charged according to the anonymity set. Wasabi allows users to a set custom fee (0.003% of
the anonymity set) from each CoinJoin transaction. The anonymity set is essentially the size of the CoinJoining
group, for example, if three people participate in a CoinJoin (with equal size inputs) for which there are three
outputs, then each of the output coins has an anonymity set of three. As mentioned above, Wasabi allows
CoinJoins of up to 100 peers, meaning that a maximum of 100 anonymity sets can be earned per CoinJoin
round, for which the fee is 0.3%. Advanced wallet users can participate in multiple rounds to further increase
their anonymity and privacy.
One problem with mixing techniques, from a privacy
perspective, is “staining” clean coins by accidentally using
them in a transaction with dirty coins. “Clean” coins are
either newly minted or have no link to illicit uses or users,
whereas “dirty” or “tainted” coins retain a history that
may be linked to illicit uses, and are thus blacklisted
from exchanges or merchants. Wasabi helps to
eliminate this problem by managing lists of clean
and dirty coins. This lists management effectively
prevents users from unintentionally staining clean coins,
nearly eliminating user errors to ensure anonymity.
Figure 2 - Wasabi's CoinJoin screen
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