Compound Interest Calculator - Calculate Your Investment Growth
Calculate the future value of your investments with compound interest.
What Is Compound Interest?
Compound interest is interest calculated on the initial principal and also on the accumulated interest from previous periods. Because later interest is calculated on a larger balance, growth can accelerate over time.
How to Use the Compound Interest Calculator
- Enter the principal amount — Type the initial amount of money invested.
- Enter the interest rate — Type the annual interest rate as a percentage (e.g., 5 for 5%).
- Enter the time period — Type the number of years the money is invested.
- Enter compounding frequency — Type how many times per year interest is compounded (e.g., 12 for monthly).
- Click "Calculate" — The tool shows the future value, total interest, and compounding frequency.
Formula
Future Value = P × (1 + r/n)^(n×t)
Where:
- P = Principal amount
- r = Annual interest rate (decimal)
- n = Number of times interest is compounded per year
- t = Number of years
Example Calculations
| Principal | Rate | Time | Compounds/Year | Future Value |
|---|---|---|---|---|
| $1,000 | 5% | 10 years | 12 (Monthly) | $1,647.01 |
| $5,000 | 7% | 20 years | 4 (Quarterly) | $20,031.96 |
| $10,000 | 8% | 30 years | 1 (Annually) | $100,626.57 |
| $2,500 | 6% | 15 years | 12 (Monthly) | $6,135.23 |
The Power of Compounding
Compound interest grows your investment exponentially over time. The longer your money is invested, the more powerful the effect. Here's an example:
- 10 years: $1,000 grows to $1,647 (64.7% gain)
- 20 years: $1,000 grows to $2,712 (171.2% gain)
- 30 years: $1,000 grows to $4,467 (346.7% gain)
Compounding Frequency Comparison
| Compounding Frequency | Future Value ($1,000 at 5% for 10 years) |
|---|---|
| Annually (1x/year) | $1,628.89 |
| Semi-Annually (2x/year) | $1,638.62 |
| Quarterly (4x/year) | $1,643.62 |
| Monthly (12x/year) | $1,647.01 |
| Daily (365x/year) | $1,648.66 |
Frequently Asked Questions
What is the formula for compound interest?
Future Value = P × (1 + r/n)^(n×t), where P is principal, r is rate, n is times per year, and t is time in years.
What is the difference between simple and compound interest?
Simple interest is calculated only on the principal. Compound interest is calculated on the principal plus accumulated interest.
What does compounding frequency mean?
It's how often interest is calculated and added to your investment. More frequent compounding leads to higher returns.
Is compound interest guaranteed?
Compound interest on investments is not guaranteed unless the investment offers a fixed rate. Stocks and other investments can lose value.
Is this compound interest calculator free?
Yes, our compound interest calculator is completely free to use. No registration, no subscription, no hidden costs.