How to Calculate EMI — Complete Guide

By Unitafy · March 2026 · 6 min read

EMI (Equated Monthly Instalment) is the fixed amount you pay every month to repay a loan. Understanding how EMI is calculated helps you compare loan offers and plan your finances better.

The EMI Formula

EMI = P × r × (1+r)ⁿ / ((1+r)ⁿ − 1)

Where:

  • P = Principal loan amount
  • r = Monthly interest rate (annual rate ÷ 12 ÷ 100)
  • n = Total number of monthly payments (years × 12)

Worked Example — Home Loan

Loan: ₹50 lakhs | Rate: 8.5% per annum | Tenure: 20 years

  • P = 5,000,000
  • r = 8.5 / 12 / 100 = 0.007083
  • n = 20 × 12 = 240
  • EMI = 5,000,000 × 0.007083 × (1.007083)²⁴⁰ / ((1.007083)²⁴⁰ − 1)
  • EMI ≈ ₹43,391 per month
  • Total payment = ₹1,04,13,840
  • Total interest = ₹54,13,840

💡 Important: Over 20 years, you pay ₹54 lakhs in interest on a ₹50 lakh loan — that's more than the principal itself! A shorter tenure or higher down payment saves significantly.

EMI for Common Loan Amounts at 8.5%

Loan Amount10 years15 years20 years
₹10 lakh₹12,399₹9,847₹8,678
₹25 lakh₹30,997₹24,618₹21,695
₹50 lakh₹61,993₹49,237₹43,391
₹1 crore₹1,23,986₹98,474₹86,782

Tips to Reduce Total Interest

  • Pay a higher down payment — reduces the principal and thus total interest
  • Choose shorter tenure — higher EMI but much less total interest
  • Make prepayments — even occasional lump sum payments reduce principal fast
  • Compare interest rates — even 0.5% difference saves lakhs over 20 years