Compound Interest
Savings growth with interest and monthly deposits.
Savings growth with interest and monthly deposits.
Savings growth with interest and monthly deposits. Fill in the fields above and the result updates instantly, together with the formula behind it.
Balance = P × (1 + i)^N + deposit × ((1 + i)^N − 1) ÷ i, with i = annual rate ÷ 12 and N = months
$10,000 plus $200 a month at 5% for 10 years grows to about $47,526.
Assumes a fixed rate, monthly compounding and deposits at the end of each month. Ignores taxes, fees and inflation; real returns vary.
Balance = P × (1 + i)^N + deposit × ((1 + i)^N − 1) ÷ i, with i = annual rate ÷ 12 and N = months. Example: $10,000 plus $200 a month at 5% for 10 years grows to about $47,526.
You enter: Starting amount; Monthly deposit; Nominal annual interest (%); Years. An example value is shown in each empty field, and the result appears as soon as the numbers are valid.
Simple interest is paid only on the original amount. Compound interest is also paid on previously earned interest, so growth accelerates over time; monthly deposits add to this effect.
Use the nominal annual rate quoted by your bank or fund. Savings rates are usually fixed for a period; investment returns vary, so try several rates to see a range of outcomes.
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