Calculators
Simple Interest Calculator
Find interest, principal, rate or time, with the working shown.
Preparing tool
How to use Simple Interest Calculator
- Choose what to find: interest, principal, rate or time.
- Enter the other values; time can be in years, months or days.
- Read the answer with each step of the SI = P × R × T ÷ 100 working, the amount, and the compound interest for comparison. Copy the working.
What are the limits of Simple Interest Calculator?
Days are counted over a 365-day year. Banks and lenders may use 360 days or compound interest instead; for deposits that compound, use the FD & RD Calculator.