paymatrix: shared expense tracking for real groups
paymatrix helps friends, flatmates, and travel groups record shared expenses, split
costs fairly, and see who owes whom.
Exact-paise expense splitting
All calculations use integer paise. Remainder paise are distributed deterministically so
every set of shares adds up exactly to the original expense.
Multiple payers for one expense
A single expense can record contributions from more than one payer instead of forcing
the group to assign the whole payment to one person.
Direct, user-confirmed settlements
paymatrix can generate a UPI QR code for a direct peer-to-peer payment. It does not hold
money or independently verify a transfer; the group records the settlement after payment
is confirmed.