Financial Calculators
Compound Interest Calculator
Enter your principal, interest rate, time period, and compounding frequency to see exactly how compound interest grows your money year by year.
Investment Details
Year-by-Year Growth
| Year | Balance | Contributions | Interest |
|---|---|---|---|
| 2026 | $7,905 | $7,400 | $505 |
| 2027 | $11,051 | $9,800 | $1,251 |
| 2028 | $14,458 | $12,200 | $2,258 |
| 2029 | $18,148 | $14,600 | $3,548 |
| 2030 | $22,145 | $17,000 | $5,145 |
| 2031 | $26,473 | $19,400 | $7,073 |
| 2032 | $31,160 | $21,800 | $9,360 |
| 2033 | $36,236 | $24,200 | $12,036 |
| 2034 | $41,734 | $26,600 | $15,134 |
| 2035 | $47,687 | $29,000 | $18,687 |
Final Amount
$47,687
After 10 years at 8% compounded monthly
Breakdown
Total Contributions
$29,000
Interest Earned
$18,687
Growth
64.4%
return on contributions
Multiplier
1.64×
What is compound interest?
Compound interest is interest calculated on both your initial principal and the accumulated interest from previous periods. Unlike simple interest (calculated only on the principal), compound interest grows exponentially — which is why Albert Einstein reportedly called it "the eighth wonder of the world."
Daily vs. monthly vs. annual compounding
More frequent compounding yields slightly more growth. Daily compounding is marginally better than monthly, which is slightly better than annual. The difference becomes more significant over long time horizons and at higher interest rates. This calculator lets you compare all frequencies side by side.
The Rule of 72 — a quick compound interest shortcut
A quick mental math shortcut: divide 72 by your annual interest rate to estimate how many years it takes to double your money. At 8% annual return, your money doubles in approximately 72 ÷ 8 = 9 years. At 6%, it doubles in 12 years.