David is a Chartered Financial Analyst and former senior credit analyst, specializing in consumer credit metrics and mortgage underwriting standards.
This 4-in-1 Debt to Income (DTI) calculator helps you see your complete financial picture. Enter any three values—Gross Monthly Income, Total Monthly Debt, Remaining Income, or DTI Ratio—and we will solve for the fourth.
Debt to Income (DTI) Calculator
Debt to Income (DTI) Formulas
R = (D / I) * 100
Solve for Income (I):
I = D + RI
or I = D / (R / 100)
Solve for Debt (D):
D = I – RI
or D = I * (R / 100)
Solve for Remaining Income (RI):
RI = I – D
or RI = I * (1 – (R / 100))
Formula Variables
- (I) Gross Monthly Income: Your total income before any taxes or deductions are taken out.
- (D) Total Monthly Debt: The sum of all your monthly debt payments (e.g., mortgage/rent, car loan, student loan, credit card minimums).
- (RI) Remaining Income: The amount of income left over after all debt payments are made (I – D).
- (R) DTI Ratio: The percentage of your gross income that goes toward paying your debts (D / I).
Related Calculators
- Loan to Value (LTV) Calculator
- Mortgage Payment Calculator
- Home Affordability Calculator
- Loan Amortization Calculator
What is Debt to Income (DTI) Ratio?
Your Debt to Income (DTI) ratio is a critical financial metric that lenders use to assess your ability to manage monthly payments and repay a new loan. It compares your total monthly debt payments to your total gross monthly income (your income before taxes).
This ratio is one of the most important factors, along with your credit score and LTV, that lenders consider when you apply for a mortgage, auto loan, or personal loan. A low DTI ratio shows that you have a good balance between your income and your debt, indicating to lenders that you are a less risky borrower.
Conversely, a high DTI ratio suggests that you are “house poor” or “over-leveraged,” meaning a large portion of your income is already committed to debt. This signals a higher risk of you defaulting on a new loan, and you may be denied credit or offered a much higher interest rate.
How to Calculate DTI (Example)
-
Find Gross Monthly Income (I)
You have a salary of $72,000 per year.
• Gross Monthly Income (I): $72,000 / 12 = $6,000 -
Calculate Total Monthly Debt (D)
Sum up all your minimum monthly payments:
• Mortgage (PITI): $1,500
• Car Loan: $300
• Student Loan: $200
• Credit Card Minimums: $100
• Total Monthly Debt (D): $2,100 -
Choose the DTI Formula
Use the standard formula to find the DTI ratio:
R = (D / I) * 100 -
Calculate the DTI Ratio
Divide your total debt by your income and multiply by 100:
R = ($2,100 / $6,000) * 100
R = 0.35 * 100 = 35%
Your DTI ratio is 35%.
Frequently Asked Questions (FAQ)
What is a “good” DTI ratio for a mortgage?
Lenders generally prefer a DTI of 36% or less. You can often get a “Qualified Mortgage” (a loan with stable features) with a DTI as high as 43%. Some government programs like FHA loans may allow for a DTI up to 50% if you have other compensating factors, like a high credit score or large cash reserves.
What is “Front-End” vs. “Back-End” DTI?
Front-End DTI (or “housing ratio”) only includes your housing-related payments (mortgage, property taxes, insurance). Lenders like to see this below 28%. Back-End DTI (which this calculator finds) includes *all* your debt payments. Back-end DTI is the more important number for loan qualification.
What debts are *not* included in DTI?
DTI generally does not include monthly living expenses like utilities, food, gas, or insurance (like health or auto insurance). It only includes installment loans, revolving credit, and housing payments.
How can I use this to find my maximum affordable debt?
Enter your Gross Monthly Income (I) (e.g., $6,000) and your target DTI Ratio (R) (e.g., 43%). The calculator will solve for Total Monthly Debt (D). This is the *maximum* total debt (including your new loan) that a lender would likely allow you to hold. You can then subtract your existing debts to see how much “room” you have for a new loan payment.