Simple Interest Calculator

Use this calculator to work out simple interest on a loan, deposit or savings amount, where interest is charged on the original sum only rather than building on itself. Simple interest is common for shorter term loans and some savings products because it is predictable: the same dollar amount of interest applies every year the rate and principal stay the same. Enter your principal, the annual interest rate as a percentage, and the time period in years. The calculator instantly returns the simple interest earned or owed, the total amount (principal plus interest), and the principal you started with, so you can see how the figures add up at a glance. It uses the standard formula: interest equals principal multiplied by the annual rate multiplied by the time in years. Adjust any of the three figures and the results update straight away, useful for comparing a short personal loan, a term deposit, or checking how a rate change affects the total you pay or earn. Because simple interest ignores any interest already accrued, it gives a lower return than compound interest over the same period, and the gap widens the longer the money is invested or borrowed. Use it alongside the compound interest calculator to see how much more a deposit could earn when interest compounds annually. As with any interest calculation, actual outcomes depend on the exact rate, term and any fees your bank or lender applies, so treat the figures here as indicative planning estimates rather than a guaranteed return or repayment amount.

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