Free online calculators

Gives stored energy and time constant for a capacitor with a series resistor.

Estimates tax owed on long-term and short-term investment gains.

Backtests a retirement withdrawal plan against historical returns and inflation.

Calculates resistor values that set the thresholds of a comparator with hysteresis.

Shows savings growth for daily, monthly or yearly compounding.

Compounded balance of a deposit over a chosen number of years and compounding period.

Official US calculator for buying-power change between two months using CPI data.

Six date tools in one page: date difference, duration, age, workdays and date arithmetic.

Counts the days, weeks and months between two dates.

Estimates what an appliance costs to run from its wattage, daily hours and price per kWh.

Official FDIC estimator for whether bank deposits are within insurance limits.

Free UK benefits calculator that estimates what a household may claim.

Estimates federal, state and local income tax for the current filing year.

Tests whether a retirement portfolio would have survived each historical market period.

Estimates free-space path loss and received power between two antennas.

Official estimate of child maintenance payments from income and care arrangements.

Official calculator for statutory paid holiday based on working pattern.

Official employer calculator for statutory redundancy pay in the UK.

Computes compound interest on a deposit or investment for a chosen compounding frequency.

Finds the number of hours and minutes between two clock times.

Affordable home price from annual income, debts and down payment.

Calculates press-fit pressure and stress for shaft and hub assemblies.

Shows how much a regular investment could grow to by retirement.

Finds resistor and capacitor values for a target cutoff frequency of RC filters.