Present value is the current worth of a future sum of money at a specified rate of return. Future cash flows are discounted at the discount rate, and the higher the discount rate, the lower the present value of the future cash flows.
Essentially, present value tells you if a sum of money today is worth more than the same amount in the future due to:
Where:
The total interest value is the difference between the future value and the present value:
This represents how much your money will grow over the given time period at the specified interest rate.
If you need ₹1,00,000 in 5 years and expect an annual return of 8%:
FV = ₹1,00,000
n = 5 years
r = 8% (or 0.08 in decimal)
PV = 100,000 / (1 + 0.08)^5 = ₹68,058
Interest Value = ₹100,000 - ₹68,058 = ₹31,942
This means you would need to invest ₹68,058 today to have ₹1,00,000 in 5 years, with a total interest gain of ₹31,942.