You have $10,000 to invest. You know the average stock market historically returns about 10% per year. But what will your money actually be worth in 20 years? You could try to calculate it manually. Year 1: $10,000 × 1.10 = $11,000. Year 2: $11,000 × 1.10 = $12,100. And repeat this 20 times. But your hands will cramp, and you might make arithmetic errors. Or you could use an investment calculator to instantly show that your $10,000 investment at 10% annual growth will become $67,275 in 20 years—earning you $57,275 in pure profit without lifting a finger. An investment calculator projects the future value of your money based on the amount you invest, the annual return rate, the time period, and how often the gains compound. It turns abstract percentages into concrete dollar amounts, helping you understand the true power of long-term investing. Investment calculators are used by retirement planners estimating nest eggs, young people understanding the value of starting early, real estate ...