How to Calculate Debt to Income Ratio (DTI)

When you apply for a home loan, the bank doesn't start by asking how much you want to borrow — it starts by checking how much of your income is already promised to other creditors. That single number, your debt-to-income (DTI) ratio, determines how much you can borrow more than almost anything else in your application. It answers one question for the lender: How many new obligations can you safely take on? Here's how to calculate it, what lenders actually look for, and how to improve it before you apply.

The formula

DTI = total monthly debt payments ÷ gross monthly income × 100

Two things to note: use gross (pre-tax) income, and use your recurring monthly debt obligations — not one-off payments.

Worked example

Suppose your gross annual income is ₹12,00,000 (₹1,00,000/month) and your existing monthly debt payments come to ₹30,000:

DTI = 30,000 ÷ 1,00,000 × 100 = 30%

That 30% tells a lender you have ₹70,000 of your monthly income unspoken for — the pool from which a new EMI would be drawn.

What counts as debt

Include:

• Loan EMIs (home, car, personal)
• Credit-card minimum payments
• Rent if you're not yet a homeowner
• Alimony and child support
• Other recurring liabilities

Exclude:

• Utilities and phone bills
• Groceries and discretionary spending
• Insurance premiums
• Taxes (deducted before you see gross income, but not "debt payments")

The key question is whether a payment is a fixed, recurring obligation to a creditor — if yes, it usually counts.

Lender thresholds

DTI	Outlook
Below 36%	Good — approvals are routine
36–43%	Fair — the typical mortgage ceiling
Above 43%	High — most lenders will say no

A common rule of thumb: keep your total EMIs within about ~36% of monthly income, and housing alone within ~28%. Lenders use these as backstops because experience shows that borrowers above them default more often.

How to improve your DTI before applying

1. Clear small, high-interest debts first — every EMI eliminated (especially credit cards) lowers the ratio fast.
2. Boost income — a raise or a side income directly shrinks the percentage, and lenders may count consistent additional income.
3. Don't open new credit before a home-loan application — even a small new EMI moves the number and can push you over the line.
4. Pay down credit-card balances — since only the minimum typically counts, but a lower balance can still help your overall file.

Why it matters for your loan amount

Banks effectively back-calculate your maximum affordable EMI from your DTI. At 36% with ₹1,00,000 monthly income, you're capped at ₹36,000 in total EMIs. Subtracting your existing ₹30,000 leaves only ₹6,000/month for a new loan — which, at a given rate and tenure, determines exactly how large a loan you can take. That's why a ₹50,000 car loan can quietly shrink your home-buying power by well over a lakh in loan amount.

Common mistakes

1. Using net income instead of gross — lenders use gross; using net inflates your ratio and scares you off.
2. Counting all credit-card balances instead of minimums — standards vary, but DTI typically uses the recurring minimum payment.
3. Ignoring rent — for non-homeowners, rent is a debt-like obligation lenders do count.
4. Applying for big-ticket credit right before a loan — the new EMI lands on your ratio at the worst possible moment.

Key takeaways

• DTI = monthly debt payments ÷ gross monthly income, expressed as a percentage.
• It's the first affordability gate lenders use — keep total EMIs near or under ~36%.
• Improving your DTI (paying down debt, raising income) directly expands your borrowing capacity.
• Don't take on new debt in the months before a major loan application.

Calculate your ratio with the Debt to Income Calculator, then see what EMI a new loan would add with the Loan EMI Calculator.

FAQ

What is a good DTI ratio?

Generally, below 36% is healthy and approvals are routine. Between 36–43% is acceptable for many mortgage lenders, and above 43% is where most will decline or offer worse terms.

Should I pay off debt or save more before buying a home?

If your DTI is near or above the ceiling, paying down debt increases your purchasing power more than additional savings — because it directly raises the amount you can borrow. If your DTI is comfortable, savings for a down payment may help more.

Does my DTI include my partner's income and debts?

Only if you're applying jointly. Lenders consider the income and debts of all co-borrowers on the application. Applying alone with a high DTI might warrant adding a co-borrower — or carrying the burden yourself.