Debt-to-Income Ratio Calculator
Work out your debt-to-income ratio from your regular debt repayments, plus a separate housing cost ratio — a useful health check before applying for a mortgage, loan or other credit.
Gross Income
Housing Cost & Monthly Debt Repayments
Monthly Debt Breakdown
Debt-to-Income (DTI) Ratio Calculator
Debt-to-income ratio (DTI) compares your regular debt repayments with your gross income. Housing costs such as rent are not debt, so this calculator shows them separately as a housing cost ratio — plus a combined housing + debt payment ratio for an overall affordability-style figure. It’s a useful thing to check before applying for a mortgage, remortgage or other credit. This calculator works out your DTI, your housing cost ratio and your combined ratio, using your own income and repayment figures.
How to Use This Calculator
- Enter your gross income — before tax, National Insurance or pension deductions — and choose whether it’s a monthly or annual figure.
- Enter your rent or mortgage payment. This is a housing cost, not a debt — it’s used to calculate your housing cost ratio and the combined housing + debt payment ratio, but it isn’t included in your debt-to-income ratio.
- Enter your other monthly debt repayments — credit cards, car finance, student loan, personal loans and anything else. Use minimum payments for credit cards, not the full balance.
- Click Calculate DTI Ratio to see your debt-to-income ratio, housing cost ratio, combined ratio, total non-housing debt and remaining income.
How Is Debt-to-Income Ratio Calculated?
The formula only includes non-housing debt:
DTI ratio = (credit cards + car loan/finance + student loan + personal loan + other debt) ÷ gross monthly income × 100
For example, if your gross monthly income is £3,000 and your non-housing debt repayments (credit cards, car finance, student loan and any other loans) come to £550, your DTI ratio is £550 ÷ £3,000 × 100 = 18.3%. Your rent or mortgage payment is not part of this figure — it’s shown separately.
Housing Cost Ratio and Housing + Debt Payment Ratio
Alongside your DTI, this calculator shows two housing-related figures:
- Housing Cost Ratio — your rent or mortgage payment against your income: housing payment ÷ gross monthly income × 100.
- Housing + Debt Payment Ratio — an overall affordability-style figure combining housing and non-housing debt: (housing payment + non-housing debt) ÷ gross monthly income × 100. This is not the same as your debt-to-income ratio, since it includes housing costs.
What Do These Ratios Mean?
There’s no single official UK threshold for DTI, and UK lenders don’t make lending decisions from a single percentage. That said, the following bands are illustrative guidance used informally across the lending industry:
| DTI Ratio | Illustrative Guide |
|---|---|
| Below 20% | Lower debt burden |
| 20% – 35% | Moderate debt burden |
| 36% – 43% | Higher debt burden |
| 44% and above | High debt burden |
These bands are illustrative rather than official UK lending thresholds. A lower DTI generally means a smaller proportion of your gross income is committed to debt repayments, while a higher DTI means a greater proportion is committed to debt. UK lenders use their own affordability criteria and consider income, debts, household spending, credit history and other factors.
Debt-to-Income vs Mortgage Affordability
DTI is a useful quick check, but it isn’t the same as a formal UK mortgage affordability assessment. UK mortgage lenders do not make lending decisions from a single DTI percentage — they consider your broader affordability, including income, debts, household spending, credit history and other circumstances, and typically apply their own stress testing and income multiples. For an estimate of how much you might be able to borrow for a mortgage, use the Mortgage Affordability Calculator.
Frequently Asked Questions
What is a good debt-to-income ratio for a mortgage?
There is no fixed UK threshold. A lower DTI generally means less of your gross income is committed to debt repayments, while a higher DTI means more is committed. The illustrative bands on this calculator are not official UK lending thresholds — UK lenders don’t make lending decisions from a single DTI percentage, and instead weigh income, debts, household spending, credit history and other circumstances. Use the Mortgage Affordability Calculator for a more specific borrowing estimate.
Does debt-to-income ratio include rent?
No. Rent and mortgage payments are housing costs, not debt, so this calculator excludes them from the debt-to-income ratio. They’re shown separately as a housing cost ratio, and combined with your other debts in the housing + debt payment ratio for an overall affordability-style figure.
Should I use gross or net income for DTI?
Gross income — your income before Income Tax, National Insurance and pension deductions. This is the standard approach used across the lending industry for debt-to-income calculations, and it’s what this calculator uses.
What debts should I include?
Include your regular non-housing debt repayments: credit card minimum payments, car loans or finance, student loan repayments, personal loans, and any other finance agreements such as buy-now-pay-later plans. Rent or mortgage payments are entered separately as a housing cost, not as debt. Everyday living costs like groceries, utility bills and council tax aren’t included in a DTI calculation.
How can I lower my debt-to-income ratio?
You can lower your DTI by paying down existing non-housing debts, avoiding new borrowing, or increasing your income. If you’re juggling several debts, our Debt Repayment Calculator compares the Avalanche and Snowball payoff methods to help you clear debts faster.