Free tools
Calculators for shared money
Working tools, not lead magnets. Nothing is stored, no account is needed, and they run entirely in your browser — including on your phone.
Bill split calculator
Split any bill between any number of people — equally, by percentage or by custom amounts — with tip and tax, and see exactly who absorbs the rounding.
- Coming soon
Rent split calculator
Divide rent between housemates by room size, income or an equal share, and compare what each method costs each person.
- Coming soon
Settle-up optimiser
Enter what everyone paid and get the smallest set of payments that clears every balance.
Why they're accurate
The same engine that runs the product
These calculators aren't simplified demonstrations. They call the exact allocation code DueCircle uses to split real expenses — integer minor-unit arithmetic, largest-remainder distribution, and an explicit record of who absorbs any leftover unit.
- Integer minor-unit arithmetic — no decimal drift
- Largest-remainder distribution — shares always sum to the total
- Every method covered by automated tests, including the awkward cases