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 put $ into an account earning % interest annually. If I leave it for years...
How much will I have in total?

Type of calculation: Calculating compound interest.
How to use the calculator: Since there isn't a dedicated "Compound Interest CALCULATOR" in our list, use a scientific or financial calculator. You can also use Excel or Google Sheets and the FV (Future Value) function.
The formula:
We want the final amount after 3 years with annual compounding.
General formula: 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
Since compounding is annual (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 = $1157.63
Interest earned: Interest = A - P = $1157.63 - $1000 = $157.63
Incomplete data. Enter all required values to see the calculations.

Answer: After 3 years, I'll have $ . That includes $ in earned interest.

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