Sumwell = calculators

Money math, worked out.

Free calculators for the big money questions: what a house or car really costs each month, how fast you can clear a credit card, how interest grows, and whether your retirement savings are on track. Every result shows the formula behind it.

M = P·r / (1 − (1+r)⁻ⁿ)Mortgage calculator

Monthly payment with taxes and insurance, plus a full amortization schedule.

APR → paymentLoan calculator

Car, personal or student loans: payment, total interest, payoff timeline.

price + tax − trade-inAuto loan calculator

Real car payment after down payment, trade-in, sales tax and fees.

balance ÷ paymentCredit card payoff

How long until you're debt-free, and how much paying extra saves.

goal → monthlySavings goal calculator

How much to save each month to hit a goal by your deadline.

A = P(1 + r/k)ᵏᵗCompound interest

See how deposits and time grow savings, with any compounding frequency.

4% ruleRetirement calculator

Project your nest egg and compare it to the savings you'll need.

(1 + i)ᵗInflation calculator

What today's prices will cost later, and what your cash will still buy.