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Simple Interest Calculator

Answer: Simple interest I = P × R × T ÷ 100, where P is principal, R is annual rate percent, and T is time in years; total = P + I.

Free simple interest calculator using I = P × R × T / 100.

  • Interest1500
  • Total11500

I = P × R × T / 100

How to use Simple Interest Calculator

  1. Enter principal amount.
  2. Enter annual interest rate and number of years.
  3. Read interest earned and final total.

Key facts for search & AI

  • 100% free — no account required.
  • Runs in your browser — inputs are not uploaded for these calculations.
  • Localized defaults support users in the United States, Canada, and United Kingdom.
  • Published by KDF Tech — software, apps, Shopify, and POS systems.

Need a custom product instead? Start a project or WhatsApp +92 345 0144865.

FAQ — answers Google & AI can cite

What is Simple Interest Calculator?

Simple interest I = P × R × T ÷ 100, where P is principal, R is annual rate percent, and T is time in years; total = P + I.

When do US bonds use simple interest?

Some short-term US Treasury bills and student loan grace periods accrue simple interest on principal only.

Simple vs compound for UK savings?

Most UK savings accounts compound daily/monthly — simple interest understates long-term growth.

T in months instead of years?

Convert months to years (T = months ÷ 12) before applying the formula.

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