Compound Interest — How Your Money Grows Over Time

Compound interest means you earn returns on your returns. $10,000 at 8% for 20 years becomes about $46,600 without adding another dollar — versus $26,000 with simple interest. Starting earlier matters more than chasing a slightly higher rate.

Rule of 72

Divide 72 by your annual return to estimate years to double. At 8%, money doubles in about 9 years.

Small fee differences compound too — a 1% higher fund fee can cost lakhs or tens of thousands over decades.

Lumpsum vs regular investing

A one-time investment compounds on the full amount from day one. Monthly SIPs add new principal over time — use both calculators to model your mix.

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