Calculate compound interest for investments, loans, and savings with visual charts. Works 100% in your browser.
See how your money grows over time with interactive charts
Daily, monthly, quarterly, or annual compounding options
Test different rates and time periods side by side
🔒 Client-Side Calculations
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Compound interest is calculated on both the initial principal and the accumulated interest from previous periods. This "interest on interest" causes wealth to grow exponentially over time.
A = Final amount
P = Principal amount
r = Annual interest rate (decimal)
n = Compounding frequency
t = Time in years
| Feature | Compound Interest | Simple Interest |
|---|---|---|
| Calculation Basis | Principal + accumulated interest | Principal only |
| Growth Pattern | Exponential | Linear |
| Long-Term Benefit | Significantly higher returns | Lower returns over time |
| Best For | Investments, savings accounts | Short-term loans, bonds |
Invest $500/month at 7% for 30 years: $566,765 (vs $180,000 invested)
$300,000 loan at 4.5% for 30 years: $546,000 total paid
$25,000 loan at 6% for 10 years: $33,900 total paid
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