CornerTools

Compound Interest Calculator

Calculate compound interest and maturity amount.

Up to 100 billion

0.1% to 100%

1 to 100 years

Final Amount
259,374
Total Interest
159,374
Principal
100,000
Principal100,000
Interest159,374

Year-by-Year Breakdown

YearOpeningInterestClosing
Year 1100,00010,000110,000
Year 2110,00011,000121,000
Year 3121,00012,100133,100
Year 4133,10013,310146,410
Year 5146,41014,641161,051
Year 6161,05116,105177,156
Year 7177,15617,716194,872

Calculates how a sum grows when interest is added to it and then earns interest itself, with the compounding frequency you choose.

Understanding the result

Final amount is the principal plus all the interest; total interest is the growth alone. Compounding more often gives slightly more interest at the same rate — the table below shows how much.

For a period past a year, the year-by-year breakdown under the result shows the balance each year opens with, the interest it earns and the closing balance. Export CSV downloads it.

How to use it

  • Principal — the sum you start with, in any currency.
  • Annual interest rate — the nominal yearly rate.
  • Time period — in years or months.
  • Compounding frequency — yearly, half-yearly, quarterly or monthly.

How it works

The annual rate is split across the compounding periods in a year, and the principal grows by that rate once per period. A time period in months is converted to years first. The final value is rounded to a whole number.

A = P × (1 + R ÷ (100 × n))^(n × t)
P = principal, R = annual rate %, n = compounding periods a year, t = years

Examples

100,000 for 10 years at 10%, compounded yearly

The final amount is 259,374, of which 159,374 is interest — against 100,000 with simple interest at the same rate.

How compounding frequency adds up

Final amount of 100,000 at 10% a year, by compounding frequency
Compounding5 years10 years20 years
Yearly161,051259,374672,750
Half-yearly162,889265,330703,999
Quarterly163,862268,506720,957
Monthly164,531270,704732,807

See also