Reckonary / Calculators / Finance calculators

Finance calculators

Money questions, answered without the noise. These calculators cover borrowing, saving, investing, and what the taxman takes — each one shows the math behind the number, not just a result.

Working out a loan or mortgage payment, planning when your savings could replace your salary, checking a take-home paycheck, or pricing a product? Pick a tool below. They're all free and need no sign-up.

FinancePaycheck (take-home pay)Net pay after federal tax, Social Security, and Medicare.Open →FinanceCompound interestGrow a balance with monthly contributions over time.Open →FinanceSimple interestInterest on a principal with no compounding.Open →Finance401(k)Project your 401(k) balance with employer match.Open →FinanceRetirement (FIRE)When your savings can replace your salary.Open →FinanceSavings goalHow much to set aside each month to hit a target.Open →FinanceROIReturn on investment as a percentage and profit.Open →FinanceInflationHow inflation changes buying power over time.Open →FinanceRule of 72Estimate how long an investment takes to double.Open →FinanceLoan repaymentMonthly payment and total interest on any loan.Open →FinanceCar loanMonthly payment on an auto loan, with trade-in and tax.Open →FinanceAmortization scheduleMonth-by-month payment breakdown and payoff date.Open →FinanceMortgagePayment, amortization, and payoff timeline.Open →FinanceRefinanceBreak-even point and savings from refinancing.Open →FinanceCredit card payoffHow long to clear a card balance and the interest cost.Open →FinanceSales taxAdd sales tax to a price to get the final total.Open →FinanceReverse sales taxWork out the price before tax from a total.Open →FinanceMarkupSet a price from cost and a markup percentage.Open →FinanceProfit marginMargin and markup from cost and selling price.Open →