How Lumpsum Returns Are Calculated
A one-time investment grows by annual compounding: Maturity = P × (1 + r)t — where P is your investment, r the expected annual return as a decimal, and t the period in years. Unlike a SIP, all of your money compounds from day one.
Example: ₹1,00,000 at 12% for 10 years → 1,00,000 × (1.12)10 ≈ ₹3,10,585 — a 3.11× multiple, of which ₹2,10,585 is pure gain. The same money at 8% would reach ₹2,15,892: two rate points compound into enormous differences over a decade.
The doubling time shown above uses the exact formula ln(2)/ln(1+r) — the Rule of 72 (72 ÷ rate) is its quick mental approximation.
Investing monthly instead? Use the SIP Calculator — or the Step-Up SIP Calculator if you increase your SIP every year. For a guaranteed-rate comparison, try the FD Calculator, and check what your gains are really worth with the Inflation Calculator.