Free tool
Debt-to-income ratio calculator
Enter gross monthly income, itemised monthly debts and a proposed housing payment to see the front-end and back-end debt-to-income ratios against the commonly cited 28/36 guideline, with limits you can edit. Print or save it for a buyer client. An estimate, not a pre-approval. Everything stays in your browser — nothing you type is sent or stored.
Like quick, simple tools? Kadapt turns listing photos into short video reels.
How the two ratios are worked out
The front-end ratio divides the proposed monthly housing payment by gross monthly income. The back-end ratio adds the other monthly debt payments (car and student loans, credit card minimums, personal loans and similar) to the housing payment and divides that total by the same income. Both are shown against a limit, 28% and 36% by default, which you can edit. The sheet also shows the largest housing payment that keeps both ratios within their limits, and how much room is left or how far over the payment is.
Things to say out loud
- Guideline, not a rule: 28/36 is commonly cited, but lenders vary and many loan programs allow higher ratios.
- Gross, not take-home: the ratios use income before tax.
- What counts as debt: lenders typically count recurring payments on a credit report. Everyday spending is not counted.
- Not a pre-approval: credit, assets, employment and the loan type all matter, and only a lender can decide.
Using it with buyers
- Enter the buyer’s real income and debts, then the payment on the home they are looking at.
- If the ratios are high, try paying down a card or loan, or a larger down payment, and compare the sheets.
- Print or save the sheet as a talking point for the lender conversation.
Related: the mortgage payment calculator for the monthly figure, the home affordability calculator, the home buyer closing cost estimator, the rent vs buy calculator, the down payment savings calculator and the first-time home buyer checklist. More in the free tools for real estate agents.
Guide: How to explain debt-to-income ratio to home buyers.
Common questions
What is a debt-to-income ratio?
It is your monthly debt payments divided by your gross (before tax) monthly income, shown as a percentage. Lenders look at it as one signal of how much more debt a borrower can carry. This calculator shows two versions: the front-end ratio, which counts only the housing payment, and the back-end ratio, which counts housing plus other monthly debts.
What is the 28/36 rule?
A commonly cited guideline says housing should be no more than 28% of gross monthly income (front-end) and total monthly debt including housing no more than 36% (back-end). It is a rule of thumb, not a law, and you can edit both limits in the calculator.
Do lenders use 28/36?
Some do. Lenders vary, and many loan programs allow higher ratios with strong credit, savings or other compensating factors, while some are stricter. Treat the result as a starting point and have the buyer talk to a lender.
What counts as monthly debt?
Recurring payments such as car loans, student loans, credit card minimum payments, personal loans and support payments. Rent, utilities, groceries and insurance premiums outside the housing payment are not normally counted. Enter the amounts that apply; the calculator does not check them.
What should go in the housing payment?
Principal and interest, property tax, homeowners insurance, HOA fees and any mortgage insurance. If you only have a principal and interest figure, the ratios will look lower than a lender’s. The mortgage payment calculator can help put the pieces together.
Does the calculator save what I enter?
No. Incomes, debts, names and contact details stay in your browser and are not sent to Kadapt, stored, or used in analytics. The only thing counted is that someone pressed the print, PNG or copy button, never what was on the sheet.
Is this a pre-approval or financial advice?
No. It is an estimating aid built from the figures you enter. It is not a pre-approval, a loan offer or mortgage, tax or financial advice. Confirm the numbers with a lender.