How to Calculate Simple Interest (2025 Guide)
Simple Interest (SI) is the most basic form of interest calculation where interest is charged only on the original principal amount. Unlike compound interest, the interest earned does not get added back to the principal.
Simple Interest Formula
SI = P × R × T / 100
- P = Principal (initial amount)
- R = Annual interest rate (%)
- T = Time period in years
Worked Example
If you deposit ₹1,00,000 at 8% for 5 years: SI = 1,00,000 × 8 × 5 / 100 = ₹40,000. Total maturity amount = ₹1,40,000.
Where is Simple Interest Used?
- Short-term personal loans
- Auto loans (some banks)
- Government savings certificates
- Student loan calculations
- Mathematics and competitive exam problems
Simple Interest vs Compound Interest
Simple interest charges interest only on the principal, making it lower than compound interest over time. For a ₹1L deposit at 8% for 5 years: SI = ₹40,000 while CI (yearly) = ₹46,933. The longer the tenure, the greater the difference.
FAQs
Q: Is FD interest simple or compound?
A: Most Indian bank FDs use quarterly compounding (compound interest), not simple interest.
Q: Can simple interest be calculated monthly?
A: Yes. Monthly SI = P × R / (100 × 12). Our calculator shows monthly interest breakdown.
What is the Simple Interest?
The Simple Interest is a comprehensive, free online tool specifically designed to help you calculate simple interest and total amount for any principal, rate, and time. Whether you are a professional or just someone looking to manage their personal finances more effectively, our Simple Interest provides instant, highly-accurate results without requiring any sign-ups or downloads.
Free simple interest calculator. Calculate SI using P×R×T/100 formula with month-wise interest schedule.
How to use this Simple Interest
Using our Simple Interest is simple and intuitive. Just input your required metrics into the form above, and the calculator will instantly map out your exact results alongside any applicable charts and comparative data. Adjust the sliders to run different "what-if" scenarios, and click the Export as PDF button at the top to securely save or print your results. All calculations happen directly in your browser, guaranteeing 100% privacy for your data.
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