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Simple Interest Calculator

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Compute interest and total with I = P × R × T — principal, rate, and years.

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Client-Side

I = P × R × T. Not compound interest.

Result

Total amount
$1,100.00
Interest$100.00

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<iframe
  src="https://tools.town/embed/simple-interest-calculator/"
  width="100%"
  height="600"
  style="border:none; border-radius:12px;"
  loading="lazy"
  title="Simple Interest Calculator">
</iframe>

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How to Use

  1. 1 Enter principal
  2. 2 Enter annual rate %
  3. 3 Enter time in years (decimals OK)
  4. 4 Read interest and total

Features

  • I = PRT formula
  • Fractional years
  • USD formatting
  • Client-side

Why it Matters

Short loans and classroom problems still use simple interest, not compound.

★★★★★

Simple interest: I = P × R × T. For compounding, use the Compound Interest Calculator instead.

Frequently Asked Questions

Simple vs compound?
Simple interest does not earn interest on interest. Use the compound calculator for that.
Months?
Enter years as a fraction — 6 months = 0.5.
Financial advice?
No — educational only.
📖

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Calculate Simple Interest on a Short Loan

Use I = PRT to find interest and total repayment on a short-term simple-interest loan.

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