The number most calculators leave out
Knowing your EMI is ₹18,000 tells you very little on its own. Whether that is comfortable or ruinous depends entirely on what you earn and what you already owe. Lenders understand this, which is why they do not just check whether you can pay — they check your FOIR.
What FOIR means
FOIR, or Fixed Obligation to Income Ratio, is the proportion of your net monthly income already committed to loan repayments. Most Indian lenders want your total EMIs, including the new one, to stay under forty to fifty percent of take-home pay. Push past that and the loan gets reduced, repriced, or declined.
Running the check yourself before you apply is useful for two reasons. It tells you roughly what a bank will approve, and — more importantly — it tells you what you should actually borrow, which is often a smaller number than what you are eligible for.
How EMI is calculated
Every lender uses the same formula. The monthly payment equals the principal multiplied by the monthly interest rate, multiplied by one plus that rate raised to the number of instalments, all divided by the same quantity minus one. The monthly rate is simply the annual rate divided by twelve.
What surprises most borrowers is the shape of the repayment. In the early years of a long loan, the large majority of each EMI is interest rather than principal. This is why prepaying early has a disproportionate effect and prepaying in the final years has very little.
Longer tenure, lower EMI, much higher cost
Extending a loan is the easiest way to make an unaffordable EMI look affordable, and it is the most expensive. Stretching a twenty-lakh home loan from fifteen years to twenty-five will drop the monthly payment appreciably — and add a very large sum in total interest, because you are paying interest on a shrinking balance for ten additional years.
Try both tenures in the calculator above and compare the total interest figures. The gap is usually larger than people expect. The general principle is to take the shortest tenure whose EMI you can sustain without strain, including in a month where something goes wrong.
Leave room for the unexpected
An EMI that consumes exactly the money you have spare is a plan with no margin. Job changes, medical costs and rate revisions on floating-rate loans all happen. If a small increase in your EMI or a two-month income gap would put you in default, the loan is too large regardless of what the ratio says.
This calculator is a general educational tool, not personalised financial advice or a loan offer. Actual EMIs depend on your lender's terms, processing fees, insurance requirements and credit assessment. Floating-rate loans change over time. For borrowing decisions, speak to your lender directly and consider consulting a SEBI-registered adviser.
Common questions
What is FOIR and why does it matter?
Fixed Obligation to Income Ratio — the share of your monthly income already going to loan repayments. Most Indian lenders want total EMIs below forty to fifty percent of net income and will reduce or decline loans that breach it.
How is EMI calculated?
P × r × (1+r)ⁿ ÷ ((1+r)ⁿ − 1), where P is principal, r is the monthly rate (annual ÷ 12 ÷ 100) and n is the number of instalments. Every lender uses this formula.
Does a longer tenure make a loan cheaper?
No. It lowers the monthly payment but raises total interest, often by a lot. Take the shortest tenure you can comfortably sustain.
Should I prepay or invest instead?
Prepaying generally wins when the loan rate exceeds your reliable after-tax investment return — almost always true for personal loans and credit cards. For low-rate home loans the comparison is closer and depends on your tax position.