Example 1
$10,000 at 5% monthly for 10 years
Grows to about $16,470, earning $6,470 in interest.
Advertisement
Top Banner 728x90 · Google AdSense
Compound Interest Calculator
See how your money grows over time. Enter your initial investment, interest rate, compound frequency, and time horizon to get started.
Investment details
See how your money grows over time.
$
%
Final balance
$20,096.61
Total interest earned
$10,096.61
Total amount invested
$10,000.00
Growth summary
Year-by-year balance breakdown
| Year | Interest | Total interest | Balance |
|---|---|---|---|
| 1 | $722.90 | $722.90 | $10,722.90 |
| 2 | $775.16 | $1,498.06 | $11,498.06 |
| 3 | $831.20 | $2,329.26 | $12,329.26 |
| 4 | $891.28 | $3,220.54 | $13,220.54 |
| 5 | $955.71 | $4,176.25 | $14,176.25 |
| 6 | $1,024.80 | $5,201.06 | $15,201.06 |
| 7 | $1,098.89 | $6,299.94 | $16,299.94 |
| 8 | $1,178.32 | $7,478.26 | $17,478.26 |
| 9 | $1,263.51 | $8,741.77 | $18,741.77 |
| 10 | $1,354.84 | $10,096.61 | $20,096.61 |
Calculator guide
How It Works
The calculator uses the compound interest formula A = P(1 + r/n)^(nt). It divides your annual rate by the number of compounding periods per year, raises that growth factor to the total number of periods, and multiplies by your initial investment. It also records the balance at each period so you can view a yearly or monthly breakdown.
Initial investment is the amount you start with. Interest rate is the annual percentage your money earns. Compound frequency sets how often interest is credited, such as annually, monthly, or daily; more frequent compounding grows slightly faster. Number of years is how long the money grows, and it has the largest effect. The same math works against you on loans: unpaid interest on a debt can compound, which is why understanding this calculator helps you see both the power of saving early and the cost of carrying a balance.
For a deeper explanation, read Understanding Compound Interest: A Beginner's Guide.
What the Numbers Mean
- Final balance
- Your projected ending amount. A high balance reflects a strong rate or long timeframe.
- Total interest
- Growth on top of your principal. If it exceeds your principal, compounding is doing heavy lifting.
- Total invested
- Your original deposit.
- Breakdown table
- Yearly or monthly balances show growth accelerating over time.
Common Scenarios
Example 2
Same deposit for 30 years
Reaches about $44,700, more than four times the start.
Example 3
Annual vs. daily compounding
On $10,000 at 5% for 10 years, daily compounding adds only about $40 more.
Frequently Asked Questions
How does compounding frequency affect growth?
More frequent compounding (daily or monthly versus annually) slightly increases overall growth since interest earns interest sooner. The difference grows more noticeable over longer time periods.
What's the impact of starting early versus investing more later?
Starting early allows compounding more time to work, often outperforming larger contributions started later. Time in the market plays a bigger role than contribution size in many cases.
Does adding regular contributions change the outcome significantly?
Regular contributions combined with compounding accelerate growth substantially compared to a single lump sum left untouched. The calculator shows how consistent additions compound over time.
What interest rate should I use for a realistic estimate?
Historical average returns for diversified investments often range between 6-8% annually, though actual results vary based on the investment type and market conditions.
Advertisement
Bottom Banner 728x90 · Google AdSense