What the calculation measures
Affordability is constrained by both housing cost and total recurring debt. The tighter selected DTI limit becomes the working payment ceiling.
How to interpret the result
Use the estimate as a scenario screen, not as a lender pre-approval.
Run scenarios instead of one answer
Change the most uncertain input and compare outcomes. A calculator is most useful when it shows sensitivity, not when one estimate is treated as a guarantee.
Limits and assumptions
Actual underwriting considers credit, loan program, taxes, insurance, reserves, income documentation and other factors.