Debt-to-Income (DTI) Calculator
Front-end (housing) and back-end (all debts) DTI. Lenders often watch 28% / 36% / 43%.
This debt-to-income calculator returns two ratios lenders use: front-end DTI, which counts only the housing payment, and back-end DTI, which counts every recurring debt. Enter gross monthly income, the proposed housing payment, and the total of other minimum payments.
DTI is the number that decides whether a mortgage application moves forward, and it is the one most buyers have never calculated. On $7,000 of gross income with $1,800 of housing and $600 of other debt, the front-end ratio is 25.7% and the back-end is 34.3% — comfortably inside conventional limits.
How to calculate debt-to-income ratio
- Add up gross monthly income before tax: salary / 12, plus stable bonus, overtime, and rental income at whatever share the lender allows.
- Add the proposed housing payment: principal, interest, property tax, insurance, and HOA dues.
- Add the minimum payments on every other debt — cards, car loans, student loans, personal loans. Not utilities or groceries.
- Front-end DTI = housing / income = 1,800 / 7,000 = 25.7%.
- Back-end DTI = (housing + other debt) / income = 2,400 / 7,000 = 34.3%.
Example
Gross income $7,000 a month, housing $1,800, car loan $450, student loan $150. Front-end 25.7%; back-end (1,800 + 600) / 7,000 = 34.3%. Add a $300 car payment and the back-end ratio rises to 38.6% — still approvable for many conventional loans, but past the 36% line where pricing starts to tighten.
DTI formula
Front-end DTI = housing payment / gross monthly income × 100. Back-end DTI = (housing + all other minimum debt payments) / gross monthly income × 100.
How to use this calculator
- Enter gross monthly income, not take-home. Lenders qualify on gross.
- Put the full housing payment in the housing field — taxes, insurance, and HOA included.
- Add the sum of minimum payments on all other debts. For a credit card, use the minimum, not the balance.
- Read both ratios: the front-end one shows whether the house itself is affordable, the back-end one whether the whole picture is.
Front-end vs. back-end
Front-end looks only at housing; back-end looks at everything. Conventional loans are usually judged on the back-end number, while FHA and some portfolio lenders look at both. A borrower at 28% front-end and 45% back-end is carrying a lot of non-housing debt, which is the risk the back-end ratio exists to catch.
The 28/36/43 lines
The old guideline was 28% front-end and 36% back-end. The 43% figure comes from the qualified mortgage rule, which treats loans above that threshold differently. Many conventional programs now allow up to 50% with compensating factors such as reserves or a strong credit score.
What counts as debt
Car loans, student loans, personal loans, child support, and minimum credit card payments all count. Utilities, phone bills, insurance premiums, and subscriptions generally do not. Student loans in deferment are usually counted at 0.5–1% of the balance, which surprises borrowers who assume deferment means zero.
How to lower it
Paying down a card lowers the minimum payment and therefore the ratio; moving the balance to another card does not. Paying off a small installment loan in full removes its payment entirely. Increasing income helps, but lenders want to see it documented for two years. Do not close old cards — the available credit helps utilization, and the payment is what counts here.
Common mistakes
- Using take-home pay instead of gross. The ratio will look far worse than the lender's calculation.
- Leaving out the car payment when testing affordability — it is usually the second-largest line in the back-end ratio.
- Assuming a pre-approval amount is a budget. The maximum is what the lender will risk, not what leaves room for saving.
FAQ
What is a good debt-to-income ratio?
Under 36% is comfortable, 36–43% is usually approvable, and above 43% needs compensating factors or a different loan program. Above 50%, most conventional lenders decline.
How is DTI calculated?
Total monthly debt payments divided by gross monthly income. The back-end version includes housing plus every other minimum payment.
Does rent count in DTI?
For a mortgage application, the proposed housing payment replaces rent. For a rental application or a personal loan, existing rent is usually included as a debt.
Do utilities count toward DTI?
No. Lenders count debt obligations with a scheduled payment — loans, cards, child support, alimony — not living expenses.
What counts as income for DTI?
Gross wages, self-employment income averaged over two years, bonuses with a history, rental income (often at 75%), and documented overtime. Unemployment, gifts, and one-off windfalls do not.
Can I get a mortgage with 50% DTI?
Sometimes, through specific programs or with strong compensating factors — reserves, a high credit score, or a large down payment. It narrows the lender pool and usually costs more.
Does paying off a credit card help immediately?
Yes, once the balance reports to the bureau. The minimum payment drops and the back-end ratio improves at the next pull, which can be within a billing cycle.