Compound Interest
Lump sum growthSee how a single lump sum grows with compound interest over time. Enter your principal, annual rate, and years to get future value and total interest earned. No periodic contributions—for regular deposits use the Interest Calculator. A year-by-year table and chart show the growth.
At 5% annual rate, balance doubles roughly every 14 years (rule of 72).
| Year | Start Balance | Interest | End Balance |
|---|---|---|---|
| Start | $10,000.00 | $0.00 | $10,000.00 |
| 1 | $10,000.00 | $500.00 | $10,500.00 |
| 2 | $10,500.00 | $525.00 | $11,025.00 |
| 3 | $11,025.00 | $551.25 | $11,576.25 |
| 4 | $11,576.25 | $578.81 | $12,155.06 |
| 5 | $12,155.06 | $607.75 | $12,762.82 |
| 6 | $12,762.82 | $638.14 | $13,400.96 |
| 7 | $13,400.96 | $670.05 | $14,071.00 |
| 8 | $14,071.00 | $703.55 | $14,774.55 |
| 9 | $14,774.55 | $738.73 | $15,513.28 |
| 10 | $15,513.28 | $775.66 | $16,288.95 |
For illustration only. Interest rates are not guaranteed. This calculator does not constitute financial advice.
About this calculator
This calculator shows how a single lump sum grows with compound interest—no periodic contributions. It is for savers and investors who want to see future value and interest earned from one initial amount (e.g. a GIC, bond, or one-time deposit) at a fixed annual rate.
Use it when you have a fixed principal and rate and want to compare different time horizons, or to illustrate the power of compounding. For savings with regular contributions, use the Interest Calculator instead. Results assume a constant rate and annual compounding; they are for illustration only.
How this is calculated
Formula
Compound interest (no contributions) uses:
FV = P × (1 + r)t
where P is the principal, r is the annual rate as a decimal (e.g. 0.05 for 5%), and t is time in years. Interest earned = FV − P.
When to use this vs the Interest Calculator
Use this for a single lump sum with no periodic deposits. If you make regular contributions, use the Interest Calculator, which compounds with contributions each period.
Assumptions
We assume the interest rate is constant and that interest compounds annually. Results are for illustration only.
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