Simple Interest Calculator - Calculate SI Online

Calculate simple interest on your investments or loans. Get instant results with our free simple interest calculator.

Last updated: June 2026 for FY 2025-26Formula verified against RBI / government guidelinesReviewed by Jashmin, Finance Professional
100% private: All calculations run in your browser. Your numbers never leave your device — no server, no storage, no account required.

Calculate Simple Interest

1,0001,00,00,000

Initial amount

%
1%30%

Annual interest rate

years
1years30years

Duration in years

Total Amount

₹1,40,000

Simple Interest

₹40,000

How to Use This Simple Interest Calculator

Using our Simple Interest Calculator is simple and takes just a few seconds. Enter your values using the sliders or input fields above, and the results will update instantly — no need to click a calculate button.

All calculations are performed in your browser using standard financial formulas. Your data is never stored or transmitted to any server, ensuring complete privacy.

The results shown are estimates based on the inputs you provide. For precise figures, consult with your bank or financial advisor. Use this tool for quick comparisons, planning, and understanding how different variables affect your financial outcomes.

Formula & Explanation

SI = (P × R × T) / 100

Where SI = Simple Interest, P = Principal amount, R = Annual interest rate, T = Time period in years. The total amount = Principal + Simple Interest.

Calculation Examples

5-Year SI

₹1 Lakh at 8% for 5 years

Interest: ₹40,000 | Total: ₹1,40,000

Benefits

  • Easy to understand
  • Quick calculation
  • Transparent interest
  • Good for short-term

Use Cases

  • Short-term loans
  • Quick comparisons
  • Education
  • Basic planning

About Simple Interest Calculator

Our Simple Interest Calculator helps you calculate interest earned or payable on a principal amount at a fixed rate for a specific period. Simple interest is calculated only on the original principal, making it straightforward to understand and compute.

Frequently Asked Questions

Simple Interest (SI) formula: SI = (P x R x T) / 100, where P = Principal amount, R = Annual interest rate (%), T = Time in years. For example, Rs 50,000 invested at 7% for 2 years: SI = (50,000 x 7 x 2) / 100 = Rs 7,000. The total amount received = Rs 57,000. Unlike compound interest, SI does not earn interest on previously accumulated interest, making it straightforward to calculate. Use the free Simple Interest Calculator on AbacusHand to calculate your exact result instantly.

Simple interest is calculated only on the original principal throughout the entire period. Compound interest is calculated on the principal plus accumulated interest each period. For Rs 1 lakh at 8% for 5 years: SI = Rs 40,000 (total Rs 1,40,000). CI (annual compounding) = Rs 46,933 (total Rs 1,46,933). The difference grows significantly over longer periods. Banks offer compound interest on FDs, making them more rewarding than SI instruments for long-term savings. Use the free Simple Interest Calculator on AbacusHand to calculate your exact result instantly.

Simple interest is used for: short-term personal loans from money lenders, certain auto loans, education loans (during the moratorium period), and some cooperative bank savings schemes. Most bank FDs and recurring deposits use compound interest. SBI personal loans and HDFC consumer durable loans often apply flat-rate (SI) interest, so the effective rate is nearly double the stated rate. Understanding which type applies helps you compare loan costs accurately. Use the free Simple Interest Calculator on AbacusHand to calculate your exact result instantly.

Using the formula SI = (P x R x T) / 100: SI = (50,000 x 7 x 2) / 100 = Rs 7,000. Total amount = Rs 57,000. If the same amount earned compound interest at 7% for 2 years: CI = Rs 7,245, total = Rs 57,245. The difference is small over 2 years but grows substantially over longer periods. For loans, always confirm whether interest is SI or CI since this significantly impacts your total repayment amount. Use the free Simple Interest Calculator on AbacusHand to calculate your exact result instantly.

Savings accounts in India technically offer compound interest, but it is calculated quarterly and credited to the account twice a year (every 6 months) by most banks. The interest rate ranges from 2.7% (SBI) to 7% (small finance banks like ESAF, Unity). Post Office Savings Accounts offer 4% per annum. Despite being compounded quarterly, the effective difference from SI is minimal over short periods. For meaningful wealth building, move surplus savings into FDs or mutual funds. Use the free Simple Interest Calculator on AbacusHand to calculate your exact result instantly.