About the EMI Calculator
An EMI calculator turns three numbers — loan amount, annual interest rate and term — into the single figure that decides whether a loan is affordable: the equated monthly instalment. This one also shows what the loan costs in total, what share of that is pure interest, and a year-by-year table tracking how much principal you have actually cleared. That table is the part most borrowers have never seen, and it explains why a home loan four years in can feel like the balance has barely moved. Add extra months if your term is not a whole number of years.
How to use the EMI Calculator
- 1
Enter the Loan amount — the sum actually disbursed to you, after any deposit or down payment.
- 2
Enter the Annual interest rate as a percentage, using the lender's nominal rate rather than the APR.
- 3
Set the Loan term in years, and use the Extra months field for terms such as 7 years and 6 months.
- 4
Read the summary stats for your monthly EMI, total interest and total repayable, then scroll to the yearly breakdown table.
What people use it for
Comparing two lender offers
A 0.4 percentage point difference sounds trivial until you price it. On 3,000,000 over 20 years, 8.5% versus 8.9% is roughly 780 more per month and well over 180,000 in extra interest across the term.
Deciding on the term length
Run the same loan over 15, 20 and 25 years. The instalment falls each time, but the total interest climbs steeply, and the interest-as-a-percentage-of-loan stat makes the trade-off obvious.
Budgeting before you apply
Most lenders want total instalments to sit under about 40 to 50% of net monthly income. Work backwards from the EMI you can sustain to the loan size worth applying for.
The amortisation formula, step by step
The instalment comes from the annuity formula: EMI = P × r × (1 + r)^n ÷ ((1 + r)^n − 1), where P is the principal, n is the number of monthly payments and r is the monthly interest rate, which is the annual rate divided by 12 and then by 100. On 500,000 at 8.5% over 20 years, r is 0.0070833 and n is 240, giving an EMI of about 4,338. Multiply that by 240 payments and you repay roughly 1,041,000 — meaning the interest alone exceeds the amount borrowed. The formula is engineered so that a constant payment exactly clears the balance on the final month. Behind each instalment the split is recalculated: interest for the month is the outstanding balance times r, and whatever is left of the payment reduces the principal. When the rate is zero the formula collapses to a straight division of principal by months, which this calculator handles as a special case.
Why the early years are almost all interest
Interest is charged on the balance still outstanding, and that balance is at its maximum on day one. In the 500,000 example, the very first instalment carries about 3,542 of interest and only around 797 of principal — roughly 82% of the payment simply pays for the use of the money. By month 120 the split is closer to even, and in the final year almost the entire instalment reduces the debt. That asymmetry has two practical consequences. First, prepayments made early are worth far more than the same amount paid late, because they cancel every future interest charge that balance would have generated. Second, selling or refinancing in the first few years leaves you with much more debt outstanding than the number of payments made would suggest. The yearly breakdown table makes this visible. Note that the figures ignore processing fees, insurance and taxes, so treat them as an estimate for comparison rather than financial advice.
Tips
- One extra instalment a year cuts a 20-year loan by roughly three to four years at typical rates, because the whole extra amount goes against principal.
- Ask lenders for the reducing-balance rate. A quoted flat rate looks lower but is close to double in real terms.
- If your loan is on a floating rate, rerun the numbers a percentage point higher to check the payment would still be manageable.