Compound Interest
How savings grow with a monthly amount, year by year.
Future value
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Type a starting amount or a monthly amount to see it grow.
Year by year
| Year | Added | Growth | Balance |
|---|
Returns are not guaranteed. Real investments rise and fall from year to year; this assumes the same rate every year, with no fees or taxes.
How this works
The balance grows month by month. Each month it earns the monthly rate, then your monthly amount is added at the end of the month. Compounded monthly, the monthly rate is the yearly rate divided by 12. Compounded daily or yearly, it is the rate that gives the same growth over a year as the yearly rate compounded that often: (1 + rate ÷ n)n ÷ 12 − 1, where n is 365 or 1. At 0% the future value is what you put in.
The effective yearly rate is what the balance grows by in a year once compounding is counted: (1 + rate ÷ n)n − 1. Doubling time is how long that rate takes to double a single deposit.
With an inflation rate, today's money is the future value divided by (1 + inflation)years: roughly what it would buy at today's prices.
Returns are not guaranteed. Savings accounts change their rates and investments rise and fall; this uses one rate for every year and leaves out fees and taxes. Amounts are worked out to fractions of a cent and shown to the cent.
What you type is saved on this device so you can come back to it. Clear all empties it, and Undo brings it back.
Saved on this device only. Nothing is sent anywhere.