Debt-to-Income (DTI) Calculator

How to use this calculator

Read the full guide: DTI basics guide

How it works

Enter gross monthly income (plus co-borrower income if applicable), recurring debt minimums, and your proposed housing payment split into principal and interest, taxes, insurance, PMI, and HOA. The calculator computes front-end DTI (housing divided by income) and back-end DTI (all debts plus housing divided by income) and shows scenario buttons to test paying down debt or lowering the payment.

Worked example

Example: $8,500 gross income, $450 cards, $400 auto, proposed housing $2,550 (PITI components). Total obligations $3,400. Back-end DTI = 40%. Front-end DTI (housing only) = 30%. Paying off $300 in card minimums drops back-end DTI to about 36.5% without changing the home price.

What counts as debt and what does not

Underwriters count the minimum monthly payment on obligations that appear on your credit report: credit cards, auto loans and leases, student loans, personal loans, and any existing mortgage. They also count court-ordered payments such as child support and alimony even though those are not credit accounts.

They do not count utilities, phone bills, insurance premiums outside your housing payment, groceries, childcare, or anything else that is simply a living expense. This surprises people, and not in a good way: a household spending $2,000 a month on daycare looks identical to one spending nothing, which is precisely why maximum approval and comfortable payment are different numbers.

The credit card treatment catches people out. Lenders use the minimum payment shown on your report, so a $9,000 balance you pay off in full every month still adds roughly $270 of counted debt. Paying the balance down before you apply, rather than just paying it on time, is one of the few fast ways to move your ratio.

The 43 percent number and why it is not a wall

43 percent gets quoted as the limit because it was the threshold in the original qualified mortgage rules. In practice, automated underwriting from Fannie Mae and Freddie Mac regularly approves conventional loans above it, often into the high 40s, when the rest of the file is strong. FHA loans can run higher still with compensating factors, and VA loans use a residual income test rather than a hard DTI ceiling.

What makes a high ratio acceptable is everything else in the application: a credit score well above the minimum, cash reserves covering several months of payments after closing, a larger down payment, or a long stable employment history. These are the compensating factors underwriters weigh, and none of them are visible in a DTI percentage.

So treat the output here as a signal rather than a verdict. Under 36 percent is comfortable almost anywhere. The 36 to 43 range is normal and routinely approved. Above 45 percent you are relying on program flexibility and a strong file, and your margin for a rate increase between pre-approval and closing gets thin.

Which lever to pull when your ratio is too high

There are only three ways to move the ratio, and they are not equally practical. You can raise income, cut debt, or lower the proposed housing payment.

Cutting debt is usually fastest, and the leverage is better than people expect. On $8,500 of monthly income, eliminating a $400 car payment frees up roughly 4.7 points of DTI, which translates to several hundred dollars of additional housing payment. Paying off a small loan entirely beats paying a little extra on several, because only the removal of the payment helps the ratio.

Lowering the housing payment works through price, down payment, or term. A larger down payment reduces the loan and often removes mortgage insurance at the same time, which is a double benefit. Be careful about draining reserves to do it, since reserves are one of the compensating factors that let a higher ratio pass.

Raising income is real but slow, and lenders want documentation. A raise needs to be on paper, bonus and commission income generally needs a two-year history, and a brand new side business usually counts for nothing yet.

Before you rely on this number

This calculator uses what you type in. A lender uses a tri-merge credit report, verified income documents, and program-specific rules about student loans in deferment, business debt you personally guarantee, and rental income offsets. Those rules change outcomes materially, and self-employed borrowers in particular should expect lenders to use net taxable income rather than gross receipts.

The practical sequence is to run scenarios here, decide the payment you want, then get a real pre-approval with documents. For the underlying concepts see debt-to-income ratio, and check how credit score interacts with pricing in credit score and your quote.

Student loans in deferment still count for most investors. Fannie Mae uses the actual payment, an income-driven plan payment, or a percentage of the balance when nothing is reporting. A zero-due line on the credit report is not a zero in the ratio. Ask the loan officer which rule they applied before you shop at the top of an approval letter. Co-signed debts count too unless you can document that someone else has been paying them for long enough to satisfy the investor.

A co-borrower moves both sides of the fraction. Their income raises the denominator and their minimum payments raise the numerator, and many conventional files are priced off the lower of the two middle credit scores. Run the ratio once with them and once without before you decide whose name belongs on the application. The official treatment of student loans and co-signed accounts lives in the Fannie Mae Selling Guide, not in a planning tool. If the guide and this page ever disagree, the guide wins.

What this calculator does not include

• Uses the payment inputs you provide, not a credit report pull.
• May not match how lenders treat student loans in deferment, business debt, or alimony.
• Program limits (FHA, VA, conventional) differ; 43% is not a universal cutoff.
• Does not verify income documentation or stability.
• Co-borrower and non-borrowing spouse rules vary by state and program.

Frequently asked questions

Which DTI do lenders care about more?

Most purchase underwriting focuses on back-end DTI. Front-end DTI still matters for payment stress.

Should I use minimum credit card payments?

Yes for planning. Lenders often use minimums from credit reports even if you pay in full each month.

What if I am self-employed?

Lenders may use taxable income averages, not gross deposits. This tool cannot model tax returns.

Can I be approved above 43%?

Sometimes, with strong credit, reserves, or automated approval. This tool flags elevated DTI, not approval.

Does housing include utilities?

No. Utilities are living expenses, not typically counted in DTI unless delinquent collections appear.

Educational tool only. Not a Loan Estimate, appraisal, tax advice, or legal opinion. Numbers are illustrative unless you enter your own verified inputs.