Debt-to-income ratio calculator

Each income is first converted to a gross monthly amount: annual ÷ 12, weekly × 52 ÷ 12, fortnightly × 26 ÷ 12, and monthly pay as it is. The sources are added together and rounded half-up to the smallest unit of your currency.

• Front-end ratio: housing ÷ monthly income × 100, rounded to one decimal place.
• Back-end ratio: (housing + Σ debt payments) ÷ monthly income × 100, rounded to one decimal place.
• Room for a new payment: max(0, target% × monthly income − commitments), rounded down so the target still holds after the new payment.
• Income needed: commitments ÷ target%, rounded up for the same reason.
• Share of income: each debt’s payment ÷ monthly income × 100, to one decimal place.

The tier is read off the back-end ratio: 36% or under is “comfortable”, over 36% up to 43% “manageable”, over 43% up to 50% “stretched” and above 50% “high”. Those cut-offs echo the figures that appear most often in US mortgage guidelines, but they are an editorial rule of thumb, not a rule any lender applies to you. An income total of zero returns an error rather than a ratio. The ratio itself has no interest, term or amortisation inside it, so it does not change with the rate on any debt; only the monthly payment matters.

Full method, rounding and tests on the methodology page

There is no single pass mark. Each lender and loan programme sets its own limit, and the limit often moves with your credit score, savings and the size of your deposit. The most-cited benchmarks come from US mortgage lending.

Conventional mortgages (United States). Fannie Mae’s Selling Guide, section B3-6-02, sets a maximum total (back-end) DTI of 36% of stable monthly income for manually underwritten loans, rising to 45% when the borrower meets the credit score and reserve requirements in its eligibility matrix. Loans run through its Desktop Underwriter system may go up to 50%. The 36% figure is also half of the long-standing “28/36 rule”, under which housing should take no more than 28% of gross income and all debts no more than 36%.

Government-backed programmes. FHA, VA and USDA loans each publish their own qualifying ratios in their handbooks, with lower standard limits that can be exceeded when compensating factors apply. Because those documents are long and change often, this page does not quote their figures; check the current handbook or ask the lender for the limit that applies to your application. The 43% option in the target list reflects the ratio that featured in the Consumer Financial Protection Bureau’s original “qualified mortgage” definition, which has since moved to a price-based test, and it remains a common reference point.

Other borrowing. Car finance, personal loans and credit cards rarely publish a DTI cut-off, but lenders in the US and Canada commonly calculate one alongside your credit history, each with its own limit. The CFPB describes DTI as one way lenders measure your ability to manage monthly payments and notes that different loan products and lenders have different limits. The debt consolidation calculator shows how replacing several payments with one changes the monthly figure that feeds this ratio, and the credit utilization calculator covers the other ratio lenders look at, balances against limits.

Outside North America the back-end ratio is a useful personal measure but not the number a lender will quote. In the United Kingdom, the FCA’s responsible-lending rules in MCOB 11.6 require a mortgage lender to assess whether the customer can afford the repayments from verified income after committed expenditure, basic household costs and a stress test for higher interest rates. The outcome is an affordability decision and a maximum loan, not a percentage. Alongside it, UK lenders apply loan-to-income multiples, so you will hear “4.5 times salary” far more often than “36%”.

Irish, Australian and New Zealand lenders work the same way: a serviceability or affordability test on the household budget, and in some of those countries regulator-set limits on the total borrowed relative to income rather than on monthly payments. A low back-end ratio still helps, because the monthly payments you enter here are exactly the committed expenditure an affordability model deducts from your income, and clearing a loan before you apply lowers both.

For that reason the tier labels are marked “rule of thumb” wherever they appear, and the housing field is simply your rent or mortgage payment: the US practice of including escrowed taxes and insurance does not apply where those are paid separately. Our guide to the debt-to-income ratio explained walks through how each country’s lenders use the figure.

Lenders count contractual debt payments: the housing payment, car loans and leases, student loans, personal loans, buy-now-pay-later instalments, the minimum payment on each credit card and line of credit, and court-ordered child support or alimony. Enter the figure you are obliged to pay each month, not the larger amount you choose to pay; if you are clearing a card faster than the minimum, that is good news for the balance but does not change the ratio a lender calculates.

Leave out living costs: utilities, phone and internet, insurance that is not part of your mortgage escrow, groceries, fuel, subscriptions and childcare. They matter to your budget and to a UK-style affordability test, but they are not debt. Income tax is not deducted either, because DTI uses gross income; a lender will normally ask for payslips, tax returns or bank statements to verify the figure.

If the result is higher than you would like, the arithmetic points to two levers. Reducing a monthly payment, by clearing a small loan outright or by consolidating several payments into one, lowers the numerator; a pay rise or a second income raises the denominator. The debt payoff calculator shows how soon a budget clears each debt, and our guide to debt consolidation loans explains when a single loan reduces the monthly total and when it only stretches the term.

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• CFPB — What is a debt-to-income ratio?
• Fannie Mae Selling Guide — B3-6-02, Debt-to-Income Ratios (36% manual, 45% with eligibility-matrix conditions, 50% DU)
• FCA Handbook — MCOB 11.6: Responsible lending and financing (affordability assessment)
• Experian — What Is Debt-to-Income Ratio? (calculation, benchmarks, no effect on credit scores)

Estimates for general information only — not financial, credit or legal advice. Your actual figures depend on your lender’s or card issuer’s exact terms, fees, minimum-payment rules, interest calculation method and any changes they make. Check your statements and speak to a qualified adviser before making decisions. Lenders define, verify and weigh debt-to-income differently; the tier labels here are a rule of thumb, not a lending decision.

Page reviewed October 9, 2026 by the DebtWren team · Methodology · Changelog · Report an error