Investment Calculator

Simple interest is earned only on your original principal. Compound interest is earned on both the principal and all previously accumulated interest. Over long time periods, the difference is enormous — a $10,000 investment at 8% simple interest for 30 years gives $34,000, while compound interest gives $100,627.

The Rule of 72 is a quick mental formula to estimate how many years it takes to double your money: divide 72 by your annual return rate. At 6% return, money doubles in approximately 12 years (72 ÷ 6). At 9%, it doubles in 8 years. This calculator shows the Rule of 72 result automatically.

The growth chart shows two lines over time: the solid line represents your growing portfolio value (including compound returns), and the dashed line shows the total amount you have invested. The gap between the two lines is your accumulated profit from compounding. Hover over any year to see exact values.

A SIP (Systematic Investment Plan) calculator computes the future value of regular fixed monthly investments with compound growth. For example, investing $500 per month at 10% annual return for 20 years results in $120,000 invested becoming approximately $380,000 in total value — a gain of over $260,000 purely from compounding.

Use a rate that reflects your expected investment vehicle. Historical averages (rough guides, not guarantees): S&P 500 index funds ~10%, diversified stock portfolio ~7–8%, bonds ~3–5%, high-yield savings ~4–5%, fixed deposits ~5–7%. Use conservative estimates for planning — it's better to be pleasantly surprised than disappointed.

No. This calculator uses a fixed assumed rate of return for illustration only. Actual investment returns vary based on market conditions, asset class, and time period. Past returns do not guarantee future results. Always consult a licensed financial advisor before making investment decisions.

Yes. All calculations run entirely in your browser using JavaScript. No financial inputs — amounts, rates, or timeframes — are ever sent to any server or stored anywhere.