House Affordability & DTI Calculator — 4 Loan Programs Compared | SILDIL
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House Affordability & DTI Calculator

Enter your income, debts, down payment, and a loan program to calculate the maximum home price you can afford — with property tax, insurance, HOA, and PMI all scaled correctly to the price, not just the payment.

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Income & Debt

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$0 $10k

Financing

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Ongoing Housing Costs

Entered as a percentage of home value per year — they scale automatically as the calculator solves for price.

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Affordability Analysis

Budget Profile
Conservative Budget
Maximum Home Price
$290,556
Down Payment
$29,056
Loan Amount
$261,500
Total Monthly Housing Payment
$2,217/mo
Front-End Ratio (housing only)
28.0%
Back-End Ratio (total debt)
33.7%

Your budget is currently limited by the front-end ratio.

Max Home Price by Loan Program

Same income, debt, rate, and down payment — different DTI ceilings.

Selected program Other programs
Monthly Payment Breakdown

How your total housing payment splits at the maximum affordable price.

Principal & Interest Tax Insurance HOA PMI
Price Sensitivity to Interest Rate

How your maximum affordable price shifts as rates move around your entered rate.

Max affordable price Your entered rate

Loan Program Comparison

See how the same income, debt, rate, and down payment translate into a different budget under each program's DTI ceilings.

ProgramDTI CeilingsMax Home PriceMonthly PaymentBinding Ratio
Conventional (28/36 Rule)28% / 36%$290,556$2,217/moFront-end
FHA Loan (31/43)31% / 43%$321,687$2,454/moFront-end
USDA Loan (29/41)29% / 41%$300,933$2,296/moFront-end
VA Loan (41% back-end)41% back-end$366,472$2,796/moBack-end

Worked Example: $95,000 Income, Conventional 28/36

A household earns $95,000 a year and carries $450 a month in other debt. They plan a 10% down payment on a 30-year loan at 6.75%, with property tax at 1.2%, insurance at 0.5%, and no HOA — all as a percentage of home value.

Under the Conventional 28/36 rule, their housing budget is capped at 28% of gross monthly income, and their total-debt budget is capped at 36%. Their front-end ratio is the one that binds.

Solving simultaneously for price, payment, tax, insurance, and PMI (since the down payment is below 20%) gives a maximum home price of $290,556, with a total monthly housing payment of $2,217.

Switching the same household to an FHA or USDA program in the table above raises the ceiling and therefore the affordable price — but also changes the monthly payment mix, since those programs carry their own insurance requirements.

How to Calculate Maximum Home Affordability from DTI Ratios

Step-by-step method to determine the maximum home price you can afford under front-end and back-end debt-to-income limits.

  1. 1. Enter income and existing debt: Input your annual gross household income and total recurring monthly debt payments, excluding rent or an existing mortgage you're replacing.
  2. 2. Choose a loan program: Select Conventional, FHA, USDA, VA, or a custom back-end DTI to set the ratio ceilings used to size your budget.
  3. 3. Enter financing assumptions: Input your expected interest rate, loan term, and down payment percentage.
  4. 4. Enter ongoing housing costs: Input property tax, homeowners insurance, and HOA dues as a percentage of home value.
  5. 5. Review your maximum price: See the maximum home price, monthly payment breakdown, and whether the front-end or back-end ratio is limiting you.

How Lenders Turn Income Into a Home Price

Lenders don't ask "what payment feels comfortable" — they run your income and debts through two ratios. Front-end DTI caps housing costs alone (principal, interest, tax, insurance, HOA, PMI) as a share of gross income. Back-end DTI caps housing costs plus every other recurring debt payment you carry.

Whichever ratio produces the smaller monthly budget is the one that actually limits you. Someone with a big car payment and student loans often hits the back-end ceiling first; someone with little other debt is usually limited by the front-end ceiling instead.

The tricky part most simple calculators skip: property tax, insurance, and HOA dues are usually set as a percentage of the home's value, and PMI is a percentage of the loan. That means the "budget" and the "price" are tangled together — a higher price needs a bigger monthly allowance for taxes and insurance, which eats into the same budget available for the mortgage payment. This calculator solves that relationship directly rather than approximating it.

Loan Programs and Their DTI Ceilings

  • Conventional (28/36) — The traditional benchmark for loans not directly insured by the government. Most conservative of the four, which is why it tends to produce the lowest maximum price for a given income.
  • FHA (31/43) — Government-insured loans with more room in both ratios, offset by required mortgage insurance premiums that raise the monthly payment for a given price.
  • USDA (29/41) — Aimed at eligible rural and suburban properties, with ceilings between conventional and FHA.
  • VA (41% back-end) — Available to eligible veterans and service members. Typically evaluates only the back-end ratio, which is why the calculator ignores the front-end limit entirely for this program.

These are commonly cited manual-underwriting figures. Automated underwriting systems can approve higher ratios in some cases, and individual lenders may apply stricter overlays — treat these numbers as a planning baseline, not a guarantee.

Frequently Asked Questions

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.

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