Calculate simple interest and the total amount for a principal, an annual rate and a number of years.
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Calculated from your inputs
Estimated value
Total contributed
Growth / interest
Illustration
Contributed Growth / interest
How this is calculated
Interest does not compound. Rate and period remain constant; taxes and fees are excluded.
Defaults are editable examples, not current provider quotes. Results are rounded for display. These are scenarios from your inputs, not live market data or investment advice.
About the Simple interest calculator
Simple interest is charged or earned only on the original principal. The interest is the same every year, because it is never added to the principal.
How the Simple interest calculator works
SI = P × r × t
SI
Simple interest
P
Principal
r
Annual rate ÷ 100
t
Years
The total amount is the principal plus the simple interest.
Worked example
Example inputs
Starting amount
₹50,000
Annual rate
9%
Time period
3 years
Calculated result
Estimated value
₹63,500
Total contributed
₹50,000
Growth / interest
₹13,500
Why use a Simple interest calculator?
Check interest on short-term loans or advances quoted at simple interest.
Compare simple and compound interest on the same terms.
Simple interest calculator FAQs
Where is simple interest used?
In some short-term loans, some deposits that pay out interest instead of reinvesting it, and in quick estimates. Most deposits and loans compound in some way.
Is simple interest the same as a flat rate?
A flat-rate loan charges interest on the full original amount for the whole term, which is simple interest. Its true cost is higher than the same reducing-balance rate; see the flat vs reducing rate calculator.
Can the period be in months?
This calculator takes whole years. For months, divide the yearly interest by 12 and multiply by the months.
Does simple interest ever beat compound interest?
For the same rate and a period longer than one compounding interval, compound interest always gives more.