AFFDmortgage
Affordability Calculator — How Much Home Can You Afford?
Home affordability calculator using the industry 28/36 rule: housing ≤ 28% of gross income, total debt ≤ 36%. Enter monthly income, existing debts, and your down payment — the tool back-solves the max home price you should target. Ideal for first-time buyers anchoring a budget.
Updated:
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How to use
- Monthly income. Gross monthly income, including stable side income.
- Monthly debts. Car loan, credit cards, student loans...
- Down payment. Cash you have ready to put down.
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Key features
28/36 rule
Default DTI cap 36%, adjustable.
Tax + ins included
Defaults: 1.1% tax, 0.35% insurance per year.
Max home price
One number you can anchor on.
Max monthly
Shown separately for reference.
Existing debts
Subtracted before sizing new mortgage.
Mobile-first
Friendly sliders on phones.
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Why Treasury.to?
- 28/36 rule
- Back-solve from income
- Tax + insurance included
- Adjustable DTI cap
- Free
- Instant
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Frequently asked questions
01What does the 28/36 rule mean?
Housing ≤ 28% of gross income; all debt (including housing) ≤ 36%. The standard for bank and Fannie Mae underwriting.
02Can I push DTI to 43%?
Yes — Qualified Mortgage loans allow up to 43%, FHA up to 50%. Adjust under Advanced.
03Does it use current rates?
Default is 7% — replace with the rate your lender quoted you.
04How much home can $100K/year afford?
Following 28/36 with a 7% rate, 30-year term and 20% down: ~$320K max home price (~$2,330 monthly housing budget). Subtract existing debts and keep cash reserves before committing.
05Should I put down more than 20%?
It eliminates PMI and lowers monthly payments, but don't drain reserves. After closing keep at least 3–6 months of expenses plus 1–2% of home value for first-year repairs. 20–25% is the typical sweet spot.
06What 'true' cost of ownership should I add?
Layer in property taxes (1–2.5%/year), home insurance (~0.35%), HOA fees, utilities, and maintenance (~1%/year of value). True total cost of ownership runs 20–40% higher than just principal and interest.
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