Interest Calculator

Calculate simple interest and compound interest for any amount.

Interest Calculator

Calculate simple interest and compound interest for any amount

% p.a.

Enter values and click Calculate

% p.a.

Enter values and click Calculate

% p.a.
Formulas Used
Simple Interest (SI)
SI = (P x R x T) / 100
Total = P + SI
Compound Interest (CI)
A = P x (1 + R/n/100)^(n x T)
CI = A - P
Effective Annual Rate
EAR = (1 + R/n/100)^n - 1
Where
P = Principal, R = Rate %
T = Time (years), n = compounds/yr

The Interest Calculator works out both simple interest and compound interest. Enter your amount, rate, and time to see how much interest you earn or owe and what the final total will be.

How to calculate interest

  1. Enter the principal amount.
  2. Type the interest rate.
  3. Set the time period.
  4. Choose simple or compound and calculate.

Simple versus compound

Simple interest is figured only on the starting amount. Compound interest is figured on the amount plus the interest already added, so it grows faster. Seeing both helps you understand savings and loans better.

Where you use it

Interest math comes up with savings accounts, fixed deposits, and loans. Whether you want to know your earnings or your cost, this calculator gives a clear figure so you can plan with confidence.