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The money lab
Five calculators for the questions that come up again and again. Each one shows its formula, the assumptions behind it and, where it uses real data, the agency that published it.
Compound growth
A starting amount, a monthly deposit and a steady yearly return. See the balance year by year and how much of it is growth rather than your own money.
Open the calculator →PricesInflation
Look back with U.S. consumer prices since 1913, or look ahead and see what a steady inflation rate does to money in a savings account.
Open the calculator →FeesFund fees
Two funds earn the same returns before fees. One charges more. Watch the gap between them grow, year after year.
Open the calculator →DebtCredit card minimums
Pay only the minimum on a credit card balance, then compare it with a fixed monthly payment. Time and interest, month by month.
Open the calculator →HousingMortgage rates
Your monthly principal and interest at today's average 30-year rate, and at every weekly average since 1971 from Freddie Mac's survey.
Open the calculator →