How to calculate compound interest total amount from principal, interest rate and time period?

Try changing the values in the input fields below to see how the calculation results update in real time!

I deposited $ into an account with an annual interest rate of %, compounded annually for years...
What will be the total amount including interest?

Type of calculation: Calculating compound interest.
Calculator usage: Since there isn't a dedicated "Compound Interest CALCULATOR" in our list, you should use a scientific or financial calculator, entering the values into the compound interest formula. You can also use a spreadsheet program (e.g., Excel, Google Sheets) and the FV (Future Value) function.
Explanation using a formula:
We are looking for the final amount after 3 years with annual compounding.
General formula for compound interest: A = P * (1 + r/n)^(n*t)
  • A – future value
  • P – principal amount
  • r – annual interest rate (as a decimal)
  • n – number of times interest is compounded per year
  • t – number of years
In our case, compounding is annual, so n=1. The formula simplifies to: A = P * (1 + r)^t
Given:
  • P = $1000
  • r = 5% = 0.05
  • t = 3 years
  • n = 1 (annual compounding)
Calculation:
A = $1000 * (1 + 0.05/1)^(1*3)
A = $1000 * (1 + 0.05)^3
A = $1000 * (1.05)^3
A = $1000 * 1.157625
A = $1157.63
Calculating the interest earned: Interest = A - P = $1157.63 - $1000 = $157.63
Incomplete data. Enter all required values to see the calculations.

Answer: After 3 years, the total amount on the deposit will be $ . The interest earned will be $ .

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