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.
About this tool
Free simple interest calculator using I = P × R × T / 100.
- Interest1500
- Total11500
I = P × R × T / 100
How to use Simple Interest Calculator
- Enter principal amount.
- Enter annual interest rate and number of years.
- Read interest earned and final total.
Why use this free tool
- 100% free — no account required.
- Runs in your browser — inputs stay on your device for these calculations.
- Mobile-friendly controls with clear, copyable results.
- Published by KDF Tech — software, apps, Shopify, and POS systems.
Need a custom product? 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.
Related free tools
Split a bill evenly between people. Use our free split bill calculator in your browser — no signup, instant results, works on mobile.
Average Down CalculatorAverage Down Calculator: New average cost after buys. Free in your browser — instant results, no signup, works on mobile.
Subscription Cost YearlySubscription Cost Yearly: Monthly → yearly subscription cost. Free in your browser — instant results, no signup, works on mobile.
Tip CalculatorSplit bills and tip like in the USA & UK — per person totals.
Tip on Pre-Tax CalculatorTip on Pre-Tax Calculator: Tip before sales tax. Free in your browser — instant results, no signup, works on mobile.
Unit Price CalculatorUnit Price Calculator: Price per oz/kg comparison. Free in your browser — instant results, no signup, works on mobile.
Invisible Character RemoverInvisible Character Remover: Strip zero-width characters. Free in your browser — instant results, no signup, works on mobile.
JavaScript FormatterJavaScript Formatter: Beautify JavaScript code. Free in your browser — instant results, no signup, works on mobile.
← All free tools · finance category · Simple Interest Calculator guide · All guides · About KDF Tech