How Much House Can I Afford?

House Affordability Calculator

There are two House Affordability Calculators that can be used to estimate an affordable purchase amount for a house based on either household income-to-debt estimates or fixed monthly budgets. They are mainly intended for use by U.S. residents.

Modify the values and click the calculate button to use
Annual household income ? salary + other incomes (before tax)
Mortgage loan termyears
Interest rate 
Monthly debt payback ?long-term debts, car, student loan, etc
Down payment
Property tax per year
HOA or co-op fee per year
Insurance per year
Debt-to-income (DTI) ratio

House affordability based on fixed, monthly budgets

This is a separate calculator used to estimate house affordability based on monthly allocations of a fixed amount for housing costs.

Budget for house ? per month
Mortgage loan termyears
Interest rate 
Down payment
Property tax per year
HOA or co-op fee per year
Insurance per year
Maintenance cost
(repair, utility etc.)
per year

RelatedMortgage Calculator | Refinance Calculator | Mortgage Payoff Calculator

In the U.S., conventional, FHA, and other mortgage lenders like to use two ratios, called the front-end and back-end ratios, to determine how much money they are willing to loan. They are basic debt-to-income ratios (DTI), albeit slightly different and explained below. For more information about or to do calculations involving debt-to-income ratios, please visit the Debt-to-Income (DTI) Ratio Calculator.

Because they are used by lenders to assess the risk of lending to each home-buyer, home-buyers can strive to lower their DTI in order to not only be able to qualify for a mortgage, but for a favorable one. The lower the DTI, the more likely a home-buyer is to get a good deal.

Front-End Ratio

The front-end debt ratio is also known as the mortgage-to-income ratio and is computed by dividing total monthly housing costs by monthly gross income.

Front-end debt ratio =
monthly housing costs
monthly gross income
× 100%

For our calculator, only conventional and FHA loans utilize the front-end debt ratio. The monthly housing costs not only include interest and principal of the loan, but other costs associated with housing like insurance, property taxes, and HOA/Co-Op Fee.

Back-End Ratio

The back-end debt ratio includes everything in the front-end ratio dealing with housing costs, along with any accrued recurring monthly debt like car loans, student loans, and credit cards.

Back-end debt ratio =
monthly housing costs + all other recurring monthly debt
monthly gross income
× 100%

This ratio is known as the debt-to-income ratio and is used for all the calculations of this calculator.

Conventional Loans and the 28/36 Rule

In the U.S., a conventional loan is a mortgage that is not insured by the federal government directly and generally refers to a mortgage loan that follows the guidelines of government-sponsored enterprises (GSE's) like Fannie Mae or Freddie Mac. Conventional loans may be either conforming or non-conforming. Conforming loans are bought by housing agencies such as Freddie Mac and Fannie Mae and follow their terms and conditions. Non-conforming loans are any loans not bought by these housing agencies that don't follow the terms and conditions laid out by these agencies, but are generally still considered conventional loans.

The 28/36 Rule is a commonly accepted guideline used in the U.S. and Canada to determine each household's risk for conventional loans. It states that a household should spend no more than 28% of its gross monthly income on the front-end debt and no more than 36% of its gross monthly income on the back-end debt. The 28/36 Rule is a qualification requirement for conforming conventional loans.

While it has been adopted as one of the most widely-used methods of determining the risk associated with a borrower, as Shiller documents in his critically-acclaimed book Irrational Exuberance, the 28/36 Rule is often dismissed by lenders under heavy stress in competitive lending markets. Because it is so leniently enforced, certain lenders can sometimes lend to risky borrowers who may not actually qualify based on the 28/36 Rule.

FHA Loans

Please visit our FHA Loan Calculator to get more in-depth information regarding FHA loans, or to calculate estimated monthly payments on FHA loans.

An FHA loan is a mortgage insured by the Federal Housing Administration. Borrowers must pay for mortgage insurance in order to protect lenders from losses in instances of defaults on loans. The insurance allows lenders to offer FHA loans at lower interest rates than usual with more flexible requirements, such as lower down payment as a percentage of the purchase price.

To be approved for FHA loans, the ratio of front-end to back-end ratio of applicants needs to be better than 31/43. In other words, monthly housing costs should not exceed 31%, and all secured and non-secured monthly recurring debts should not exceed 43% of monthly gross income. FHA loans also require 1.75% upfront premiums.

FHA loans have more lax debt-to-income controls than conventional loans; they allow borrowers to have 3% more front-end debt and 7% more back-end debt. The reason that FHA loans can be offered to riskier clients is the required upfront payment of mortgage insurance premiums.

VA Loans

Please visit our VA Mortgage Calculator to get more in-depth information regarding VA loans, or to calculate estimated monthly payments on VA mortgages.

A VA loan is a mortgage loan granted to veterans, service members on active duty, members of the national guard, reservists, or surviving spouses, and is guaranteed by the U.S. Department of Veterans Affairs (VA).

To be approved for a VA loan, the back-end ratio of the applicant needs to be better than 41%. In other words, the sum of monthly housing costs and all recurring secured and non-secured debts should not exceed 41% of gross monthly income. VA loans generally do not consider front-end ratios of applicants but require funding fees.

Custom Debt-to-Income Ratios

The calculator also allows the user to select from debt-to-income ratios between 10% to 50% in increments of 5%. If coupled with down payments less than 20%, 0.5% of PMI insurance will automatically be added to monthly housing costs because they are assumed to be calculations for conventional loans. There are no options above 50% because that is the point at which DTI exceeds risk thresholds for nearly all mortgage lenders.

In general, home-buyers should use lower percentages for more conservative estimates and higher percentages for more risky estimates. A 20% DTI is easier to pay off during stressful financial periods compared to, say, a 45% DTI. Home-buyers who are unsure of which option to use can try the Conventional Loan option, which uses the 28/36 Rule.


If you cannot immediately afford the house you want, below are some steps that can be taken to increase house affordability, albeit with time and due diligence.

Working towards achieving one or more of these will increase a household's success rate in qualifying for the purchase of a home in accordance with lenders' standards of qualifications. If these prove to be difficult, home-buyers can maybe consider less expensive homes. Some people find better luck moving to different cities. If not, there are various housing assistance programs at the local level, though these are geared more towards low-income households. Renting is a viable alternative to owning a home, and it may be helpful to rent for the time being in order to set up a better buying situation in the future. For more information about or to do calculations involving rent, please visit the Rent Calculator.

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