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Instant calculation
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Online Calculator
Simple interest calculator
Calculate simple interest earned on an investment or charged on a debt.
Interest generated
150.00
Final total
1,150.00
Formula: Interest = Principal × Rate × Time
Information
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Data are processed in your browser and do not need to be sent to a server.
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Frequently asked questions
What is the formula of simple interest?
Interest = Principal × Rate × Time.
Should I enter the rate as a percentage?
Yes. For example, enter 5 to represent 5%.
Is time expressed in years?
Yes. This version uses years and supports decimals.
Does it include the starting capital in the total?
Yes. The final total is the principal plus the interest earned.