Free Simple Interest Calculator
Work out simple interest and the total amount in seconds — time in years, months or days.
- 100% free
- No limits
- No upload
- No watermark
- Works on mobile
How to use the Simple Interest Calculator
- 1
Enter values
Principal, rate and time.
- 2
Read the result
Interest and total update instantly.
Why use Qu-Outil's Simple Interest Calculator
Fast, private and free — with no limits.
Years, months or days
Enter the time in whichever unit you have.
Instant and private
Everything happens in your browser as you type. Your text is never sent to a server.
Free and unlimited
No sign-up, no limits and no ads in the way. Use it as often as you like.
Works on any device
Fully responsive — works the same on a phone, tablet or computer.
Simple Interest Calculator — frequently asked questions
What is the simple interest formula?
SI = P × R × T ÷ 100, with T in years.
Is it free?
Yes — free with no sign-up and no limits.
Is my text stored or uploaded?
No. Everything runs in your browser; nothing you type is sent to a server or saved.
Help keep Qu-Outil free
I build and run these tools in my free time and keep them free for everyone — no ads, no sign-up. If they helped you, buy me a chai or coffee via Google Pay or any UPI app. Your support keeps me building more free tools. Completely optional.
samarthdalela@oksbiThe button opens Google Pay, PhonePe or Paytm on your phone. On desktop, scan the QR.
Scan to pay ₹50
Works with any UPI app