Compound interest calculator
See how a lump-sum investment grows with compounding — and how long it takes to double. Free, private (runs in your browser) — no sign-up.
Amount invested
Return / interest
%/yr
Years
Compounding
Currency
Future value
₹3,10,585
Invested
₹1,00,000
Growth
₹2,10,585 (3.11×)
Rule of 72: money doubles in about 6.0 years at 12% a year.
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What is the rule of 72?
Divide 72 by the yearly return to estimate how many years it takes to double your money. At 12% a year, money doubles in about 6 years.
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