Debt-to-income ratio calculator
Enter your gross monthly income, your housing payment and your other monthly debt payments. The debt-to-income ratio calculator shows your back-end and front-end DTI, compares it with the 36% guideline for manually underwritten conventional mortgages and works out how much more monthly debt – and loan amount – fits under it.
Example: Gross monthly income 6,000 · Monthly housing payment 1,500 · Other monthly debt payments 500 · Interest rate for a new loan 6.5 % per year · Term of a new loan 30 years → Debt-to-income ratio (back-end): 33.33%. Source: CFPB – What is a debt-to-income ratio? (monthly debt payments ÷ gross monthly income). Updated: .
How it is calculated
How to calculate your debt-to-income ratio
DTI = total monthly debt payments ÷ gross monthly income. The CFPB’s example: 2,000 in monthly debt payments on a 6,000 gross monthly income is a DTI of 33%. Count minimum payments on all loans and credit cards, plus the housing payment; everyday bills such as utilities and groceries are not debts.
- Back-end DTI: all monthly debts including housing ÷ gross income – the number lenders mean by “DTI”.
- Front-end (housing) ratio: only the housing payment ÷ gross income.
What DTI do lenders accept?
Limits differ by loan program. For conventional loans sold to Fannie Mae, the Selling Guide sets a maximum of 36% for manually underwritten loans, up to 45% with strong credit and reserves, and up to 50% when approved through its automated Desktop Underwriter. Lower is always better: it leaves room for savings and surprises.
| Gross income | Housing | Other debts | DTI |
|---|---|---|---|
| 6,000 | 1,500 | 500 | 33.3% |
| 6,000 | 1,800 | 900 | 45% |
| 4,500 | 1,200 | 300 | 33.3% |
How much loan fits?
The calculator turns the room under the guideline into a loan amount: loan = payment × (1 − (1 + i)−n) ÷ i, with i = annual rate ÷ 12 and n = months. At 6.5% over 30 years, each extra 100 a month supports about 15,800 of loan. Taxes, insurance and HOA dues are part of the housing payment, so leave room for them.
How to lower your DTI
Pay down balances with high minimum payments, avoid new credit before applying, or add a co-borrower’s income. Under Fannie Mae’s rules, installment debts with ten or fewer payments left are generally not counted.
Frequently asked questions
How do you calculate debt-to-income ratio?
Add up all monthly debt payments – housing, car, student loans, minimum credit card payments – and divide by gross monthly income. 2,000 of payments on 6,000 of income is 33%.
What is a good debt-to-income ratio for a mortgage?
Lower is better. Fannie Mae allows up to 36% for manually underwritten loans, up to 45% with strong credit and reserves, and up to 50% with automated approval.
Is DTI based on gross or net income?
In the US, on gross monthly income – before taxes and deductions.
Does rent count in debt-to-income ratio?
When you apply for a mortgage, lenders use the new housing payment instead of your current rent. For other loans, some lenders include rent – ask how they count it.
What is the difference between front-end and back-end DTI?
Front-end counts only the housing payment; back-end counts all monthly debts including housing. Lenders focus mainly on the back-end ratio.
Sources and legal basis
- CFPB – What is a debt-to-income ratio? (monthly debt payments ÷ gross monthly income)
- Fannie Mae Selling Guide B3-6-02, Debt-to-Income Ratios (36 % / 45 % manual, 50 % DU)
As of:
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