What are 28/36 DTI ratios?

Front-end 28% is housing (P&I, tax, insurance, HOA) over gross monthly income. Back-end 36% is housing plus other monthly debts. The tighter of the two is the housing budget on this page.

Do lenders still use 28/36?

It is the classic conservative sketch. Many conventional files go to 45%+ with compensating factors. FHA and VA use different back-end tests. This is not a pre-approval.

Does the down payment change the loan?

Yes. Max home = max loan + down payment. Taxes, insurance, and HOA come out of the housing budget before P&I is inverted into a loan.

Runs in your browser · Last updated 7 September 2026

Free Mortgage Affordability Calculator (US, 28/36 DTI)

Free US mortgage affordability calculator. Classic 28/36 DTI — max home, max loan, and which ratio binds. Browser tool — nothing is uploaded.

Gross annual income ($)Other monthly debts ($)Note rate %Term (years)Down payment ($)Annual property tax ($)Annual homeowners insurance ($)Monthly HOA ($)

Housing budget is the tighter of 28% of gross monthly income and 36% minus other debts. Conventional underwriting can go higher with compensating factors — this page is the classic 28/36 sketch, not a pre-approval.

Max home price

$400,153

Max loan

$340,153

Max P&I / month

$2,150.00

Housing budget

$2,800.00

Binding ratio

28% front-end

DTI at max

28.0% / 32.0%

How to use this tool

Enter gross income, other monthly debts, rate, term, and down payment.
Add annual tax and insurance (and HOA if any).
Read max home, max loan, and which ratio binds.

Worked example

$120,000 income, $400 other debts, 6.5% for 30 years, $60,000 down, $6,000 tax and $1,800 insurance: the 28% housing cap is $2,800/month and the 36% leftover after debts is $3,200, so 28% binds. After tax and insurance, leftover P&I becomes the max loan. For extra principal on a loan you already have, use the extra payment mortgage calculator.

Frequently asked questions

What are 28/36 DTI ratios?: Front-end 28% is housing (P&I, tax, insurance, HOA) over gross monthly income. Back-end 36% is housing plus other monthly debts. The tighter of the two is the housing budget on this page.
Do lenders still use 28/36?: It is the classic conservative sketch. Many conventional files go to 45%+ with compensating factors. FHA and VA use different back-end tests. This is not a pre-approval.
Does the down payment change the loan?: Yes. Max home = max loan + down payment. Taxes, insurance, and HOA come out of the housing budget before P&I is inverted into a loan.
Uploaded?: No.