Simple Interest Calculator

Simple interest is one of the most fundamental financial concepts taught in Nepali schools from class 7 onwards and used in everyday banking. The formula SI = (P × R × T) / 100 calculates the interest earned or owed on a principal amount (P) at a fixed annual rate (R) over a given time period (T in years). While compound interest is more common in modern banking, simple interest still applies in many real-world situations in Nepal — short-term personal loans between individuals, cooperative society deposits, agriculture loans from rural development banks, and fixed-period government bonds. Students preparing for SEE (Secondary Education Examination) and NEB class 11–12 mathematics encounter simple interest problems extensively in their curriculum. This calculator handles the computation instantly: enter your principal, annual interest rate, and time period, and it returns the total interest earned and the maturity amount (principal + interest). It is also useful for quick mental-math verification — if someone offers you 12% annual return on a Rs 1,00,000 deposit for 2 years, you can instantly confirm that the simple interest would be Rs 24,000, giving you Rs 1,24,000 at maturity. Teachers use it to generate practice problems, and parents helping children with homework find it invaluable for checking answers. Beyond academics, understanding simple interest helps Nepalis evaluate informal lending terms (common in rural communities), compare short-term deposit schemes, and verify interest calculations on receipts from cooperatives and microfinance institutions that still use simple interest methods.