Debt-to-Income Ratio Calculator

Most borrowers don't calculate their DTI until a lender does it for them, at which point it's too late to fix. Running this calculator before applying gives you time to act on what you find.

Pre-mortgage planning. Mortgage underwriters pull your DTI the moment they run your credit. If you're over 36%, you'll either be denied or offered worse terms. Running this calculator 6–12 months before you want to buy a home gives you a concrete target: which debts to pay off, whether to increase income, and how large a mortgage payment you can realistically support.

Benchmark your current financial health. Even if you're not buying a home, DTI is a clean measure of financial stress. Below 20%: strong. 20–36%: healthy. 37–43%: caution. Above 43%: high strain. Knowing your number helps you prioritize whether to focus on debt paydown or income growth.

Model different scenarios. Adjust the inputs to answer "what if" questions: what if I pay off my car loan? What if I add freelance income? What if I move to a lower-cost apartment? The calculator recalculates instantly, turning these questions into concrete numbers.

Find the maximum affordable payment. The Max Debt for 36% DTI output answers a question home-buyers ask constantly: "how much can I afford?" It gives you the maximum total monthly debt burden at the 36% benchmark, from which you can subtract your existing non-housing debts to find your maximum mortgage payment.

Prospective homebuyers. Anyone planning to apply for a mortgage in the next 12 months should run this calculator immediately. Knowing your DTI tells you whether you're lender-ready or need to reduce debt first. A DTI of 44% with a 6-month runway can be brought to 36% by paying off a car loan or reducing credit card balances.

Renters evaluating home affordability. The calculator's Max Debt for 36% DTI output, minus your current non-housing debts, gives your maximum sustainable mortgage payment. From that number, you can work backward with the Mortgage Calculator to find the maximum home price you qualify for.

Borrowers considering additional loans. Adding a car loan, personal loan, or home equity line of credit to an already-loaded debt profile can push DTI above the lender threshold. Run this calculator with the proposed new payment included to see the impact before applying.

People working through debt payoff strategies. The calculator shows exactly how much each debt reduction improves your DTI. Paying off a $300/month car payment on a $4,500/month income drops DTI by 6.7 percentage points, a concrete return on the debt payoff effort.

Financial coaches and loan officers. The shareable URL feature allows you to pre-fill a client's actual debt and income numbers and share the calculation directly.

Back-End DTI is the primary output, the percentage of your gross monthly income going to all monthly debt payments combined. This is the number mortgage lenders and credit card companies evaluate. Below 20%: excellent financial position, maximum borrowing capacity. 20–28%: good. 29–36%: acceptable but watch it. 37–43%: high, lenders may ask for compensating factors. Above 43%: over-leveraged, most conventional mortgage paths close at this level.

Front-End DTI isolates your housing cost (mortgage or rent) as a percentage of income. The conventional mortgage benchmark is 28%. If your front-end DTI is already above 28% on rent alone, adding a mortgage payment at the same amount or higher will make qualification difficult without significant income growth.

Total Monthly Debt Payments is the raw dollar sum of all your obligations, a useful sanity check to compare against what you thought you were paying. Many people are surprised to find their total is higher than their mental estimate once all minimums are added up.

Max Debt for 36% DTI is the maximum total monthly debt payment that would keep you at the 36% threshold on your current income. Subtract your current non-housing debts from this number to find your maximum supportable housing payment. This is the most actionable output for home purchase planning.

1. Enter your Gross Monthly Income, your pre-tax household income from all sources, divided by 12. Include salary, freelance income, rental income, and any regular part-time earnings. Do not subtract taxes or deductions.

2. Enter Monthly Mortgage / Rent, your current housing payment (or your proposed future mortgage payment if modeling a home purchase). Include only the base payment, not utilities.

3. Enter Monthly Car Payments, the sum of all vehicle loan payments you are obligated to make monthly. Do not include insurance or fuel.

4. Enter Monthly Student Loans, the actual required monthly payment on all student loans. If on an income-driven plan, use the current IDR payment, not the full standard payment. Note that mortgage lenders may impute a higher payment, see the FAQ below.

5. Enter Monthly Credit Cards, the minimum required payments on all credit card accounts, not your actual payment habits. Paying more than the minimum doesn't change your DTI calculation.

6. Enter Monthly Other Debt, child support, alimony, personal loans, home equity loans, and any other recurring installment obligations.

7. Interpret the outputs, check Back-End DTI against the 36% benchmark. Review Max Debt for 36% DTI and subtract your non-housing debts to find your maximum supportable housing payment. If your DTI is above 43%, identify which single debt payoff would have the greatest impact.