Simple Interest Calculator
Calculate simple interest and total amount for any period.
Parameters & Inputs
Calculated Breakdown
No calculation yet
Set your values on the left and click Calculate to view instantaneous results.
About Simple Interest Calculator
Simple Interest Calculator computes interest as principal × rate × time, with no compounding. It is the basis for most short-term loans, personal borrowings and statutory interest.
The difference from compound interest grows quickly: at 10% over ten years, simple interest costs about half of what compounding does.
How to use Simple Interest Calculator
- 1
Enter the principal
The amount borrowed or lent, not including fees.
- 2
Set rate and duration
Annual rate and the term in years or months.
- 3
Read the total
Interest amount and total repayment are shown separately.
Questions about Simple Interest Calculator
What is the formula?
SI = P × R × T / 100, with R as the annual percentage and T in years.
How do I handle months?
Convert to years: 6 months = 0.5. Using 30-day months introduces a small error for long terms.
Why is my bank charging more?
Most loans use reducing-balance interest, which is calculated differently. Use the EMI calculator for those.
Does it include fees?
No. Processing fees and insurance are separate and should be added to the true cost.
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Last updated November 2026. Files are processed on FilePlume's own hardware and deleted within 60 minutes; nothing is used for training.