Mortgage Affordability Calculator
Estimate a home price target using a housing debt-to-income assumption and expected ownership costs.
Enter your numbers
Use the defaults as a sample scenario, then edit any field to compare outcomes.
Planning estimate only. Results update locally in your browser.
Understand the result
Use this section for the assumptions, tradeoffs, charts, and questions to ask before acting.
Educational estimate only — not financial, legal, tax, mortgage, or lending advice. Confirm lender rules, taxes, insurance, penalties, and legal/tax implications with qualified professionals.
What this means
This estimate uses front-end housing dti because your housing-payment cap is tighter than the total-debt cap, then reserves room for ownership costs. A 8.5% stress rate lowers the home-price estimate to about $339,340, and cash plus the selected buffer totals about $102,065.
Decision memo
Copy or print a local-only worksheet for lender shopping, household planning, or refinance comparisons.
| What changes | Baseline | New scenario | Difference |
|---|---|---|---|
| Monthly DTI cap | Front-end cap $2,800 | Back-end cap $3,000 | Front-end housing DTI sets $2,800 |
| Cash planning | $91,865 | $102,065 | $10,200 buffer added |
| Rate stress test | $395,488 | $339,340 | 8.5% test rate |
- Baseline
- Front-end cap $2,800
- New scenario
- Back-end cap $3,000
- Difference
- Front-end housing DTI sets $2,800
- Baseline
- $91,865
- New scenario
- $102,065
- Difference
- $10,200 buffer added
- Baseline
- $395,488
- New scenario
- $339,340
- Difference
- 8.5% test rate
| Front-end DTI target | Max payment | Home price | Stress-test price | Back-end DTI |
|---|---|---|---|---|
| 25% | $2,500 | $372,690 | $320,599 | 31% |
| 28% | $2,800 | $395,488 | $339,340 | 34% |
| 31% | $3,000 | $424,835 | $363,464 | 36% |
- Max payment
- $2,500
- Home price
- $372,690
- Stress-test price
- $320,599
- Back-end DTI
- 31%
- Max payment
- $2,800
- Home price
- $395,488
- Stress-test price
- $339,340
- Back-end DTI
- 34%
- Max payment
- $3,000
- Home price
- $424,835
- Stress-test price
- $363,464
- Back-end DTI
- 36%
Lender-shopping checklist
- Ask each lender for the same rate-lock period, points or credits, APR, loan type, and estimated payment components.
- Compare total cash to close, lender fees, third-party fees, prepaid taxes/insurance, escrow reserves, and any mortgage/default-insurance treatment.
- Confirm whether quoted taxes, insurance, HOA/condo fees, reserves, and repair budget still fit your monthly budget after closing.
- Save the quote date, expiration date, and required documents so the affordability estimate can be reconciled against real pre-approval terms.
Watch-outs
- Affordability ratios do not know your comfort level, job risk, repairs, childcare, or lifestyle goals.
- Insurance paths vary by market and loan program; below-20% down payments often change both qualification and monthly payment.
- A pre-approval can differ from this estimate because lenders apply detailed rules, stress tests, reserves, and documentation checks.
Formula
Max housing payment uses the tighter of front-end housing DTI and back-end total DTI after existing monthly debt.
Max principal and interest = max housing payment − tax/insurance/HOA estimate, with a separate PMI/default-insurance path when applicable.
Estimated loan amount is the loan principal supported by that payment, rate, and term. Cash-to-close, maintenance reserve, emergency buffer, and stress-test estimates are planning placeholders.
Worked example
With $120,000 income, $600/month debt, $80,000 down, 6.5% rate, and 28% housing DTI, estimated affordable home price is around the mid-$400k range after ownership-cost assumptions.
Important disclaimer
This is an educational calculator, not financial, legal, tax, or professional advice. Decisions can depend on taxes, fees, local rules, rates, risk, and your personal situation.
FAQ
Is this lender approval?
No. Lenders use their own underwriting rules, credit standards, documentation, and debt calculations.
Why include taxes and insurance?
Because they reduce the room available for principal and interest within a monthly housing budget.
What DTI should I use?
Lower is safer. This tool lets you test assumptions; it is not advice.
Get a better answer from the Mortgage Affordability Calculator
- Start with the example values to see how the tool behaves.
- Swap in your own numbers, even if they are rough first-pass estimates.
- Change one input at a time so you can see what actually moves the result.
What the result means
The result is a home-budget estimate, not a lender promise. It helps you see the monthly payment, cash pressure, and interest tradeoff before you shop or commit.
How to use it
Compare a comfortable case with a stretched case. The gap tells you how much room you have if the rate, taxes, insurance, or closing costs move.
What can change it
Principal and interest are only part of home cost. Taxes, insurance, HOA or condo fees, repairs, mortgage insurance, and closing costs can change the real answer fast.
Example to try
Start with lender-style debt-to-income limits, then lower the target until the payment leaves room for repairs, utilities, and emergency savings.
Assumption to challenge
Approval and comfort are different. A maximum qualified price can still be too tight for your real monthly budget.
Verify next
Check income treatment, recurring debts, credit obligations, cash-to-close, reserves, tax/insurance estimates, and any stress-test rule.
Common uses
- Estimate an affordable price range.
- Model debt-to-income assumptions.
- Pair with monthly budget planning.
Common questions
Is the Mortgage Affordability Calculator private?
Yes. CalcShelf calculators run without an account, do not save calculator entries, and do not put raw inputs into shareable URLs or analytics events.
How accurate is the Mortgage Affordability Calculator?
It is a home-finance estimate, not a lender quote. Rates, taxes, insurance, fees, insurance premiums, and underwriting rules can change the real payment or approval result.
What should I check after using the Mortgage Affordability Calculator?
Verify rate, fees, taxes, insurance, lender rules, cash to close, and any mortgage insurance before acting.
Which calculator should I try next?
Use the related calculators below to cross-check the same decision from another angle before you act.
Method behind the estimate
Mortgage calculators use standard amortization and payment math with user-entered rates, terms, taxes, insurance, and fee assumptions.
Why the detail matters
Results are estimates. Lender rules, payment frequency, penalties, taxes, mortgage insurance, closing costs, and local law can change the real answer.
Privacy guardrail
Your calculator values are for you. CalcShelf does not require an account, save calculator entries, put your numbers into shareable URLs, or use raw inputs as analytics events.
Copy or print safely
Use any copy, print, or worksheet controls as local handoff tools for your own notes, supplier calls, lender questions, or implementation checklist. They are there to help you explain the result to a human.
Before acting
Treat the result as a decision draft, not a verdict. Recheck the source numbers, run a downside case, and verify the real-world rule, quote, label, or spec that controls the final answer.
Last reviewed: May 11, 2026. See methodology and editorial policy for formulas, assumptions, rounding, review approach, and limitations. For borrowing decisions, confirm lender rules, rates, taxes, fees, and legal requirements.