Add your starting balance, monthly savings, expected return, and timeline.
Future Value
$44,665.27
Monthly compounding.
Total Principal
$29,000.00
Total Contributions
$24,000.00
Interest Earned
$15,665.27
Balance Composition
64.9% principal / 35.1% interest
Set a savings goal with a deadline → Savings Goal Calculator
Track annual contributions, earned interest, and ending balance.
| Year | Starting Balance | Contributions | Interest Earned | Ending Balance |
|---|---|---|---|---|
| 1 | $5,000.00 | $2,400.00 | $439.97 | $7,839.97 |
| 2 | $7,839.97 | $2,400.00 | $645.27 | $10,885.24 |
| 3 | $10,885.24 | $2,400.00 | $865.41 | $14,150.65 |
| 4 | $14,150.65 | $2,400.00 | $1,101.47 | $17,652.12 |
| 5 | $17,652.12 | $2,400.00 | $1,354.59 | $21,406.71 |
| 6 | $21,406.71 | $2,400.00 | $1,626.01 | $25,432.72 |
| 7 | $25,432.72 | $2,400.00 | $1,917.05 | $29,749.77 |
| 8 | $29,749.77 | $2,400.00 | $2,229.13 | $34,378.90 |
| 9 | $34,378.90 | $2,400.00 | $2,563.77 | $39,342.67 |
| 10 | $39,342.67 | $2,400.00 | $2,922.60 | $44,665.27 |
Apply realistic savings plans to see the impact of time and consistency.
Compound interest is the process of earning returns on both your original deposits and the interest that has already accumulated. Unlike simple interest, which only applies to your initial principal, compound interest creates a snowball effect — as your balance grows, each period's interest amount grows with it. This is why compound interest is often called the most powerful force in personal finance.
With simple interest, a $10,000 deposit at 5% earns exactly $500 per year, every year. With compound interest, you earn $500 in year one, then $525 in year two (5% of $10,500), then $551.25 in year three, and so on. Over 30 years, that same deposit grows to $43,219 with compounding versus just $25,000 with simple interest — a difference of over $18,000 from interest earning interest.
Core formulas
FV_principal = P x (1 + r/n)^(n x t)
FV_contributions = PMT x [((1 + r/n)^(n x t) - 1) / (r/n)]
Where P is initial amount, PMT is monthly contribution, r is annual rate, n is compound periods per year, and t is years.
This calculator supports daily, monthly, quarterly, and annual compounding. More frequent compounding applies interest to your balance more often, meaning earned interest gets reinvested sooner and begins generating its own returns. The difference between monthly and annual compounding is modest over short periods but can become meaningful over decades, especially at higher interest rates.
Time is the most powerful variable in the compound interest equation. Someone who invests $200 per month starting at age 25 will accumulate significantly more than someone who invests $400 per month starting at age 35, even though the late starter contributes more total dollars. This is because early contributions have more compounding periods to grow. The key takeaway: start as early as possible, even with small amounts.
Results from this calculator are nominal, pre-tax estimates. Inflation, investment fees, taxes on gains, and performance variability are not included. Use multiple rate scenarios to build a realistic range of outcomes for your planning.
Common questions about growth projections, assumptions, and interpretation.
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This calculator provides estimates for educational purposes only and is not financial advice. Actual returns vary by market performance, account fees, contribution timing, and taxes. Consult a qualified financial professional for personalized planning advice.