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See how your money grows over time
See how compound interest accelerates your wealth.
Include regular contributions in calculations.
View detailed breakdown by year.
Daily, monthly, quarterly, or annual.
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Compound interest is interest calculated on both your initial principal AND the accumulated interest from previous periods. Unlike simple interest (calculated only on principal), compound interest makes your money grow exponentially over time - earning "interest on interest."
The compound interest formula is: A = P(1 + r/n)^(nt), where A = final amount, P = principal, r = annual interest rate, n = compounds per year, t = time in years. Our calculator handles this automatically, including monthly contributions.
For monthly compounding, divide the annual rate by 12 and compound each month. Example: $10,000 at 6% compounded monthly means each month you earn 0.5% (6%÷12) on the current balance, then next month's interest is calculated on the new, higher balance.
For quarterly compounding, divide the annual rate by 4 and compound 4 times per year. Each quarter, interest is calculated on your principal plus all previously earned interest. Our calculator lets you select quarterly frequency.
More frequent compounding = faster growth. Daily compounding earns slightly more than monthly, which earns more than quarterly or annually. The difference becomes more significant with higher interest rates and longer time periods.
It depends on the account. Savings accounts often compound daily. Credit cards typically compound daily too. Mortgages usually compound monthly. Check your account terms - our calculator supports daily, monthly, quarterly, and annual compounding.
Interest rates are quoted as annual rates (APR or APY), but may compound at different frequencies. A 6% annual rate compounded monthly is different from 6% compounded daily. Our calculator shows the actual growth based on your compounding choice.
The Rule of 72 is a quick mental math trick: divide 72 by your annual interest rate to estimate years to double your money. At 6% interest, money doubles in ~12 years. At 8%, it doubles in ~9 years. At 12%, it doubles in ~6 years.
Enter your initial investment, add any regular monthly contributions, set your expected annual return rate (7% is a common stock market average), choose your time horizon, and click Calculate. The calculator shows year-by-year growth.
Most investments benefit from compound growth. Stocks grow through reinvested dividends and price appreciation. Bonds earn interest that can be reinvested. Savings accounts compound interest. Our calculator works for any investment scenario.
Yes! Any account that pays compound interest (most do) helps your money grow faster than simple interest. High-yield savings accounts, money market accounts, and certificates of deposit all use compound interest.
For savings accounts: 0.5-5% APY. For bonds: 3-6%. For stock market investments: 7-10% historical average (though past performance doesn't guarantee future results). For loans: use your actual loan APR.
Use the Rule of 72: divide 72 by your interest rate. At 6% = 12 years to double. At 8% = 9 years. At 10% = 7.2 years. Our calculator shows year-by-year growth so you can see exactly when you'll reach milestones.
This calculator focuses on growth. For drawdown calculations (living off investments), you'd need a retirement withdrawal calculator. Enter your target amount here to see how long it takes to reach your goal.
For monthly interest: divide annual rate by 12, multiply by your balance. For $10,000 at 6% APR: $10,000 × (6%÷12) = $50/month initially. With compound interest, each month's interest is higher as your balance grows.
Interest payment = Balance × (Annual Rate ÷ Periods per year). For $100,000 at 5% paid monthly: $100,000 × (5%÷12) = $416.67 monthly interest. Over time, as you pay down principal, interest decreases.
Interest = Principal × Rate × Time. For compound interest, this calculation happens repeatedly, with each period's interest added to the principal before the next calculation. Our calculator automates this for any time period.
Yes! Enter your loan amount as principal, set monthly payment to 0, use your loan's APR as the interest rate. The result shows how much you'd owe if you made no payments - useful for understanding how quickly debt grows.
1) Enter your starting amount. 2) Add monthly contribution amount (optional). 3) Set annual interest rate. 4) Choose time period in years. 5) Select compounding frequency. 6) Click Calculate to see your future value and year-by-year breakdown.
Yes! Our calculator uses the standard compound interest formula used by banks and financial institutions. Results are mathematically accurate. Real-world returns may vary due to variable rates and market conditions.
Yes! We use the standard compound interest formula with monthly contribution adjustments. Results match financial calculators and spreadsheets. For exact figures, consult your financial institution.
Yes! Our calculator is 100% free with no limits. Calculate as many scenarios as you want - no signup required. All calculations happen in your browser for privacy.