Q: What is the difference between front-end and back-end DTI?
Front-end DTI is the share of your gross monthly income that goes toward housing costs alone: principal, interest, property tax, homeowners insurance, HOA dues, and PMI if applicable. Back-end DTI adds every other recurring monthly debt on top of housing — car loans, student loans, credit card minimums, and similar obligations.
Q: Which DTI limit actually determines how much house I can afford?
Whichever ratio produces the smaller housing budget. If your other debts are high, the back-end limit usually binds first; if you carry little debt, the front-end limit usually binds first. This calculator checks both automatically and shows which one is binding for your numbers.
Q: Why does the maximum price change when I adjust property tax or HOA fees?
Property tax, insurance, and HOA dues are typically set as a percentage of the home's value, so a pricier home costs more to tax and insure every month. That eats into the same housing budget your mortgage payment competes for, which is why raising any of these fields lowers the maximum affordable price, not just the payment.
Q: When does PMI apply, and how does it affect affordability?
Private mortgage insurance (PMI) generally applies whenever the down payment is below 20% of the home price. Because PMI is itself a percentage of the loan balance, it also scales with price and further reduces the maximum home you can afford at low down payments.
Q: What DTI limits do conventional, FHA, VA, and USDA loans use?
This calculator uses commonly cited manual-underwriting ceilings: Conventional loans follow the 28/36 rule, FHA loans allow 31% front-end and 43% back-end, USDA loans allow 29% front-end and 41% back-end, and VA loans typically cap only the back-end ratio at 41%. Actual limits vary by lender and by whether the loan is run through an automated underwriting system, which can allow a higher DTI.
Q: Is a lower DTI always better?
A lower DTI generally means more room in your budget for savings, emergencies, and rate increases if you carry an adjustable-rate loan, and it can also unlock better interest rates. It isn't inherently "better" in every case, but it is lower-risk, which is why conservative loan programs cap it more tightly than others.
Q: How much does a bigger down payment increase my affordable price?
A bigger down payment lowers the loan amount needed for the same price, which lowers the P&I payment per dollar of home value, and once you cross the 20% threshold it also removes PMI entirely. Both effects mean the same monthly housing budget stretches to a higher price.
Q: Should I use my gross income or take-home pay for this calculator?
Use gross (pre-tax) income. Lenders calculate DTI ratios against gross monthly income, not take-home pay, so that is the figure this calculator — and any lender you apply with — will use.