How much house can I afford to buy?

A safe rule of thumb is to keep your mortgage payment under 28% of your gross monthly income and your total debts under 36%. Use this calculator with your exact down payment and interest rate to see real math.

Does debt lower how much house I can afford?

Yes - every dollar you spend on car payments, student loans, and credit cards directly reduces your maximum allowed mortgage payment. Lenders look at your existing monthly debt to calculate your back-end Debt-to-Income (DTI) ratio.

Is it safe to stretch my housing budget?

Lenders will often approve you up to a 43-45% debt-to-income ratio, which leaves very little margin for savings or emergencies. A "comfortable" housing budget sits closer to 25% of your gross income.

Can I afford a $400k house if I have debt?

It depends on your income and total debt load. With $500/month in existing debt on $110k income, you technically qualify for a $400k home — but your back-end DTI of ~43% leaves little financial buffer. Lenders will approve it, but it is a stretch.

How does existing debt affect mortgage approval?

Lenders use your back-end DTI — all monthly debt payments divided by gross income. The limit is typically 43%. Every $100/month in existing debt reduces your maximum mortgage amount by approximately $20,000–$22,000.

What is the debt-to-income ratio for a $400k mortgage?

A $400k home with 10% down and 6.8% rate has an all-in payment of roughly $2,800/month. To keep back-end DTI under 43%, you need gross income of at least $100,000–$115,000 depending on your existing debt load.

Should I pay off debt before buying a house?

If your back-end DTI is above 43%, paying off debt first may be required to qualify. Even if you qualify, reducing monthly debt obligations before buying improves your cash flow and financial stability as a homeowner.

Affordability Scenario

Can I Afford a $400,000 House With Existing Debt?

With $500/mo in existing debt on $110k income:

Back-end DTI limit (43%): $3,958/mo total debt allowed

Remaining for housing: ~$3,458/mo

$400k home all-in payment: ~$2,800/mo

✓ Technically qualifies — but leaves little breathing room.

Lenders don't just look at your income — they look at your total debt load. With $500/month going to a car and student loans, your borrowing power drops significantly. Use the calculator below to see your exact numbers.

Income & Debts

Annual Income

Monthly Debt

Loan & Down Payment

Down Payment

Interest Rate

Loan Term (Years)

Ongoing Housing Costs

Property Tax Rate

Monthly Insurance

Monthly HOA

Lending Assumptions

Front-End DTI LimitYour housing costs (mortgage, tax, insurance) should stay under this % of your gross monthly income. Lenders typically cap this at 28%.

Back-End DTI LimitAll monthly debt payments (housing + car + student loans + credit cards) as a % of gross income. Most lenders allow up to 43%.

Want to know more?

What Salary Do I Need for a Mortgage?

See exactly what income you need to qualify in 2026, plus how debt changes your numbers.

Affordability Estimate

You can afford a home around

$346,000

Based on your current income, debt, and housing cost assumptions.

Comfortable target$346K

Stretch maximumup to $380K

Monthly Housing Budget

$2,570

Comfortable

This appears to be within a comfortable borrowing range.

Estimated Loan Amount

$306,000

Estimated Cash Needed (Down + Closing)

$50,000

Estimates based on your inputs. Actual results may vary. Terms →

Calculation Breakdown

Estimated Principal & Interest$1,990
Estimated Property Taxes$350
Estimated Homeowner's Insurance$100
Estimated HOA$0
Estimated PMI$130
Front-End Ratio Used28.00%
Back-End Ratio Used33.45%

Save this scenario

Keep track of multiple affordability setups.

Next steps

Calculate the exact cash needed to close on this home Validate your decision before committing to buy

Frequently asked questions

How Debt Kills Buying Power

Every $100/mo in existing debt reduces your max mortgage by roughly $20,000–$22,000. At $500/mo in debt payments, you've already lost $100k+ in borrowing capacity before a lender sees your application.

Front-End vs Back-End DTI

Front-end DTI: housing costs only — lenders cap at 28%. Back-end DTI: all debt including housing — capped at 43%. With existing debt, your back-end limit becomes the binding constraint, not your income.

3 Ways to Improve Your DTI

1. Pay off the smallest debt first — frees up monthly cash fast. 2. Increase your down payment — smaller loan = lower payment. 3. Add a co-borrower — combines income and lowers your DTI ratio instantly.

Related guide

How Debt Affects Mortgage Approval

→

See exactly which debts count, how monthly payments reduce your maximum home price, and how to fix a high DTI before applying.

Related calculators

Can I Afford a $400k House? (No Debt) →

See the base scenario if you have no monthly debt payments.

Monthly Payment on a $400k House →

Calculate exact monthly costs including taxes, insurance, and PMI.

Home Affordability Calculator →

Find exactly how much house you can afford based on your income and debts.

Income to House Price Calculator →

See how your income and DTI translate directly into borrowing power.

Estimates based on your inputs. Actual results may vary. Terms →