Calculate simple interest
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Computed in your browser from the same formulas the full app uses — it is not saved and does not factor in every detail (taxes, exact compounding dates, fees) the way a saved scenario does. Sign in to save, share, or view history →
Simple interest uses SI = P × r × t / 100, where P is principal, r is the annual rate, and t is time in years.
Simple interest = Principal × Rate × Time / 100, where the rate is the annual interest rate and time is in years.
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