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Compound Interest Calculator
Calculate compound interest with flexible compounding frequencies, optional regular deposits, and support for all major currencies.
Initial investment or deposit amount
Additional deposit each compounding period
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Final Amount
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Principal
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Interest Earned
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Total Deposits
Principal + Deposits: —
Interest Earned: —
Year-by-Year Growth
Frequently Asked Questions
Compound interest is interest calculated on both the initial principal and the accumulated interest from previous periods. Unlike simple interest (which is only on the principal), compound interest grows exponentially over time. This is why Albert Einstein reportedly called it the "eighth wonder of the world."
A = P(1 + r/n)nt, where:
• A = Final amount
• P = Principal (initial investment)
• r = Annual interest rate (decimal)
• n = Number of times compounded per year
• t = Time in years
For regular deposits, the future value of annuity formula is added: FV = D × [((1 + r/n)nt − 1) / (r/n)]
• A = Final amount
• P = Principal (initial investment)
• r = Annual interest rate (decimal)
• n = Number of times compounded per year
• t = Time in years
For regular deposits, the future value of annuity formula is added: FV = D × [((1 + r/n)nt − 1) / (r/n)]
More frequent compounding yields higher returns because interest starts earning interest sooner. For example, on a ₹1,00,000 principal at 10% for 10 years:
• Annually: ₹2,59,374
• Quarterly: ₹2,68,506
• Monthly: ₹2,70,704
• Daily: ₹2,71,791
The difference between daily and monthly is relatively small, but annually vs. monthly can be significant over long periods.
• Annually: ₹2,59,374
• Quarterly: ₹2,68,506
• Monthly: ₹2,70,704
• Daily: ₹2,71,791
The difference between daily and monthly is relatively small, but annually vs. monthly can be significant over long periods.
Simple interest: Calculated only on the original principal. Formula: SI = P × r × t. It grows linearly.
Compound interest: Calculated on principal + accumulated interest. It grows exponentially. Over 20 years at 8%, ₹1 lakh becomes ₹2.60L with simple interest but ₹4.66L with compound interest (annually).
Compound interest: Calculated on principal + accumulated interest. It grows exponentially. Over 20 years at 8%, ₹1 lakh becomes ₹2.60L with simple interest but ₹4.66L with compound interest (annually).
The Rule of 72 is a quick mental math shortcut to estimate how long it takes for money to double. Simply divide 72 by the annual interest rate.
• At 6%: 72 ÷ 6 = ~12 years to double
• At 8%: 72 ÷ 8 = ~9 years to double
• At 12%: 72 ÷ 12 = ~6 years to double
This rule is most accurate for rates between 6% and 10%.
• At 6%: 72 ÷ 6 = ~12 years to double
• At 8%: 72 ÷ 8 = ~9 years to double
• At 12%: 72 ÷ 12 = ~6 years to double
This rule is most accurate for rates between 6% and 10%.
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⚠️ Disclaimer: This calculator provides estimated projections based on a fixed interest rate and compounding frequency. Actual returns may vary based on market conditions, fees, taxes, inflation, and other factors. Interest rates on deposits and investments fluctuate over time. This tool is for educational and illustrative purposes only and does not constitute financial advice. Please consult a qualified financial advisor before making investment decisions.