Investment Calculator

Calculate the future value of your investments with compound interest. See how your money can grow over time with regular contributions and the power of compounding.

Investment Details

$
The amount you're starting with
$
Amount you'll add each month
%
Historical S&P 500 average: ~10%
years
How long you'll invest
How often interest compounds

Investment Summary

Future Value
$0
After 0 years
Initial Investment
$0
Total Contributions
$0
Total Interest Earned
$0

Portfolio Composition

Initial (0%)
Contributions (0%)
Interest (0%)
0x
Money Multiple
0%
Total ROI
$0
Avg Monthly Interest

Year-by-Year Breakdown

Year Starting Balance Annual Contribution Interest Earned Ending Balance

Investment Growth Over Time

Total Invested
Interest Earned

Compare Scenarios

Conservative (4%)

$0
Bonds, CDs, Savings

Moderate (7%)

$0
Balanced Portfolio

Aggressive (10%)

$0
Stocks, Index Funds

Compound Interest Formula

A = P(1 + r/n)nt + PMT × [((1 + r/n)nt - 1) / (r/n)]
A = Future value of investment
P = Principal (initial investment)
r = Annual interest rate (decimal)
n = Compounding frequency per year
t = Time in years
PMT = Regular payment amount

The Power of Starting Early

Investor A - Starts at 25

  • Invests $200/month for 40 years
  • Total invested: $96,000
  • At 7% return: $524,968
VS

Investor B - Starts at 35

  • Invests $200/month for 30 years
  • Total invested: $72,000
  • At 7% return: $243,994

10 years of delay costs over $280,000 in this example, even though the total invested differs by only $24,000. Time in the market beats timing the market!

Smart Investment Tips

Start Early

Time is your greatest asset. Even small amounts compound significantly over decades.

Stay Consistent

Regular monthly contributions through dollar-cost averaging reduce risk and build wealth.

Diversify

Spread investments across different asset classes to reduce risk and optimize returns.

Minimize Fees

Low-cost index funds often outperform actively managed funds after fees.

Reinvest Dividends

Automatically reinvesting dividends accelerates compound growth substantially.

Stay the Course

Avoid emotional decisions during market volatility. Long-term investors are rewarded.

Historical Average Returns

S&P 500

~10%
Annual average (1926-2023)

Bonds

~5%
Annual average (long-term)

Savings Account

~0.5%
Current average APY

Inflation

~3%
Historical average

Past performance doesn't guarantee future results. These are historical averages and actual returns may vary significantly.

Frequently Asked Questions

What is compound interest?

Compound interest is interest calculated on both the initial principal and the accumulated interest from previous periods. It's essentially "interest on interest," which makes your money grow exponentially rather than linearly.

How does compounding frequency affect my returns?

More frequent compounding leads to slightly higher returns. Daily compounding will yield more than annual compounding for the same rate. However, the difference is usually small for typical investment rates.

What's a realistic expected return rate?

For a diversified stock portfolio, 7-10% is historically reasonable. Conservative investments like bonds may return 3-5%. Always plan with multiple scenarios and remember that returns fluctuate year to year.

Should I account for inflation?

Yes! Inflation reduces purchasing power over time. A 7% return with 3% inflation gives you roughly 4% real return. Our calculator's advanced options let you see inflation-adjusted values.

How much should I invest monthly?

A common guideline is to save/invest 15-20% of your income. Start with whatever you can afford consistently, even if it's small. You can increase contributions as your income grows.

What about taxes on investment gains?

This calculator shows pre-tax returns. Tax-advantaged accounts (401k, IRA, Roth IRA) can help reduce tax impact. Consult a tax professional for personalized advice.