Future Value Calculator
Calculate how your investments will grow over time
Last updated: January 2026
Investment Details
Annual equivalent: $1,200.00
Investment Growth Over Time
Investment Breakdown
Power of Compound Growth
The S&P 500 has historically returned around 10% annually. Regular contributions combined with compound returns can significantly grow your wealth over time.
Understanding Future Value
Compound Interest Explained
Compound interest is interest earned on both your original principal and on previously accumulated interest. Unlike simple interest (which is calculated only on the principal), compound interest creates exponential growth over time. The more frequently interest compounds — monthly vs. annually, for example — the faster your money grows. Albert Einstein reportedly called compound interest "the eighth wonder of the world," and for good reason: it is the single most powerful force in long-term wealth building.
The Rule of 72
The Rule of 72 is a quick mental shortcut to estimate how long it takes your money to double. Simply divide 72 by your annual rate of return. At 8%, your money doubles in approximately 9 years. At 6%, it takes about 12 years. At 10%, roughly 7.2 years. This formula works best for rates between 4% and 12% and gives you an intuitive sense of how different return rates affect long-term growth.
Why Starting Early Matters
Time is the most critical factor in growing wealth through compound interest. Someone who invests $200/month starting at age 25 will have significantly more at age 65 than someone who invests $400/month starting at age 35 — even though the late starter contributes more total money. This is because the early investor has an extra decade for compound growth to work. Every year you delay investing, you lose the most powerful compounding years at the end of your timeline.
Adjusting for Inflation
Inflation erodes the purchasing power of money over time. A sum worth $1 million in 30 years at 3% average inflation would have the purchasing power of only about $412,000 in today's dollars. To calculate your real (inflation-adjusted) future value, subtract the expected inflation rate from your assumed rate of return. If you expect 8% returns and 3% inflation, use 5% as your real rate of return for a more accurate picture of future purchasing power.
Frequently Asked Questions
What is future value?
Future value is the projected worth of an investment or sum of money at a specific date in the future, based on an assumed rate of return. It accounts for compound interest and helps you understand how much your savings or investments will grow over time.
How do regular contributions affect future value?
Regular contributions dramatically increase future value due to compounding. For example, investing $500/month at 7% annual return grows to approximately $580,000 over 30 years, even though your total contributions are only $180,000. The rest is compound growth.
What rate of return should I assume for long-term investments?
The S&P 500 has returned an average of about 10% annually before inflation (roughly 7% after inflation) over the long term. Conservative estimates use 6-7%, moderate use 8%, and aggressive use 10%. Always factor in your risk tolerance and investment mix.
What is the Rule of 72?
The Rule of 72 is a quick way to estimate how long it takes your money to double. Divide 72 by your annual rate of return — at 8%, your money doubles in approximately 9 years. At 6%, it takes about 12 years. This simple formula works best for rates between 4% and 12%.
How does inflation affect future value?
Inflation reduces the real purchasing power of your future savings. A sum worth $1 million in 30 years at 3% average inflation would have the purchasing power of only about $412,000 in today's dollars. To see your real (inflation-adjusted) future value, subtract the expected inflation rate from your assumed rate of return.