How to Calculate Debt to Income Ratio: Formula & Example
Learn how to calculate debt to income ratio by adding monthly debt payments, dividing by gross income, and using lender-style examples clearly today too.
Debt-to-income ratio is one of the first numbers lenders check when deciding whether you can afford a new loan. Knowing how to calculate debt to income ratio helps you understand how much of your monthly income is already committed to debt payments. It is especially important before applying for a mortgage, car loan, personal loan, or refinance. The formula is simple: add monthly debt payments, divide by gross monthly income, and convert to a percentage.
What Is Debt-to-Income Ratio?
Debt-to-income ratio, or DTI, compares monthly debt payments with monthly gross income. The Consumer Financial Protection Bureau defines DTI as monthly debt payments divided by gross monthly income, and notes that lenders use it to assess your ability to manage payments.
The formula is:
DTI = (Monthly Debt Payments รท Gross Monthly Income) ร 100
How to Calculate Debt to Income Ratio
Follow these steps:
- Add all required monthly debt payments.
- Find your gross monthly income before taxes.
- Divide debt payments by gross income.
- Multiply by 100.
Use our free DTI Calculator to calculate the ratio quickly.
Step-by-Step Example
Suppose your monthly debts are:
| Debt | Monthly Payment |
|---|---|
| Mortgage or rent counted by lender | $1,500 |
| Auto loan | $350 |
| Student loan | $250 |
| Credit card minimums | $150 |
| Personal loan | $200 |
| Total Monthly Debt | $2,450 |
Your gross monthly income is $7,000.
DTI = ($2,450 รท $7,000) ร 100 = 35%
Your debt-to-income ratio is 35%.
What Counts as Monthly Debt?
Usually include required monthly payments:
| Include | Usually Do Not Include |
|---|---|
| Mortgage payment | Groceries |
| Car loans | Utilities |
| Student loans | Streaming subscriptions |
| Credit card minimums | Cell phone bill |
| Personal loans | Insurance not tied to loan underwriting |
| Child support or alimony | Optional savings contributions |
Lenders may count items differently, so ask the specific lender for underwriting rules.
Front-End vs. Back-End DTI
| Type | Formula | Used For |
|---|---|---|
| Front-end DTI | Housing payment รท gross income | Mortgage affordability |
| Back-end DTI | All monthly debts รท gross income | Overall debt load |
Back-end DTI is the broader number because it includes all recurring debt payments.
DTI Quick Reference
| Monthly Debt | Gross Monthly Income | DTI |
|---|---|---|
| $1,000 | $5,000 | 20% |
| $1,500 | $5,000 | 30% |
| $2,000 | $5,000 | 40% |
| $2,500 | $5,000 | 50% |
This table shows why income and debt payments both matter. The same debt can be manageable for one borrower and too high for another.
How to Improve DTI
You can lower DTI by reducing monthly debt obligations or increasing gross income:
- Pay down credit cards or loans.
- Refinance only if it truly lowers required monthly payments.
- Avoid new debt before applying for a mortgage.
- Increase income with overtime, side work, or documented raises.
- Consider a less expensive home, car, or loan amount.
The Mortgage Calculator can estimate housing payments, and the Loan Calculator can help compare debt payoff or borrowing scenarios.
Common Mistakes
Using take-home pay instead of gross income will make DTI look higher than lenders usually calculate it.
Including every monthly bill can distort the ratio. DTI focuses on debt payments, not all living expenses.
Using total credit card balances instead of minimum monthly payments is another common error. For DTI, lenders usually consider the required monthly payment.
Ignoring co-signed loans can cause surprises. If you are legally responsible, a lender may count it.
Also remember that DTI is not a full budget. It does not show groceries, utilities, childcare, insurance, or savings goals, so a loan can pass a DTI test and still feel uncomfortable.
Frequently Asked Questions
How to calculate debt to income ratio for a mortgage?
Add your expected housing payment and all other monthly debt payments, then divide by gross monthly income. Multiply by 100. Mortgage lenders may review both front-end DTI for housing alone and back-end DTI for all debts combined.
What is a good debt-to-income ratio?
Lower is generally better because it leaves more room in your budget. Many lenders prefer lower DTIs, but exact limits vary by loan type, credit score, down payment, and lender rules. A high DTI can make approval harder or reduce the amount you can borrow.
Do utilities count in DTI?
Utilities usually do not count as debt payments in a standard DTI calculation. DTI typically includes required payments on loans, credit cards, mortgage debt, student loans, auto loans, and similar obligations. Lenders may still consider overall budget stability separately.
Is DTI based on gross or net income?
DTI is usually based on gross income, which is income before taxes and deductions. This is why the number may look different from a personal budget based on take-home pay. For day-to-day affordability, you should still consider net income.
How can I lower my DTI fast?
Paying down debts that have monthly payments can help, especially credit cards or small loans. Increasing documented income can also help. Avoid opening new loans before applying for major credit, because new payments raise DTI.
The Bottom Line
To calculate debt-to-income ratio, divide total monthly debt payments by gross monthly income and multiply by 100. The result helps lenders evaluate borrowing capacity and helps you see how much of your income is already committed.
Use our free DTI Calculator to calculate your ratio before applying for a loan or mortgage.
How to Calculate: Step-by-Step Guide
Sum Monthly Debt Payments
Add up all your required monthly debt obligations like mortgage/rent, car loans, student loans, and credit card minimums.
Find Gross Monthly Income
Identify your total monthly income before taxes and other deductions are taken out.
Divide Debt by Income
Divide your total monthly debt payments by your gross monthly income.
Convert to Percentage
Multiply the decimal result by 100 to get your Debt-to-Income (DTI) ratio percentage.
Assess Borrowing Capacity
Compare your result to lender benchmarks (often preferring DTI below 36% to 43%) to see where you stand for new loans.