How to use
- Replace the example inputs with your loan and property figures.
- Select Calculate to update the estimate and any schedule.
- Change one assumption at a time, then compare the result with the earlier scenario.
How this calculation works
The tool takes the smaller of two budgets: gross monthly income times the housing ratio, or gross monthly income times the total-debt ratio minus other debt payments. It subtracts entered property costs, then solves for the loan that the remaining P&I budget can support.
P&I budget = min(income × housing limit, income × debt limit − other debts) − property costs
Worked example
Illustrative inputs — not a quote or a local average.
- Gross annual income
- $100,000.00
- Other monthly debt payments
- $500.00
- Housing ratio limit
- 28 %
- Total debt ratio limit
- 36 %
- Cash down payment
- $80,000.00
- Interest rate
- 6.5 %
- Loan term
- 30 years
- Annual property tax
- $4,200.00
- Annual home insurance
- $1,800.00
- Monthly HOA dues
- $0.00
- Monthly mortgage insurance
- $0.00
Price supported by selected limits: $370,053.17. Supported loan amount: $290,053.17. Monthly housing budget: $2,333.33.
Reading the result
The price combines the supported loan and your cash down payment. It is a planning ceiling under your assumptions, not a recommendation to spend the maximum. Test a lower housing ratio if income varies or you have major expenses that debt ratios do not capture.
Before acting on the estimate
The annual tax and insurance inputs stay fixed while price changes. Update them for the actual property. Closing costs are not taken from the down-payment input, so reserve those funds first. No lender approval, assistance program or loan limit is assumed.
Questions, answered
Are 28% and 36% lender requirements?
No. They are editable example planning limits.
Why can the supported loan be zero?
Entered debt or property costs may use all of the selected monthly budget.