Borrowing Capacity Calculator
Written by Thierno Sadou Diallo, formula verified per our methodology • Last checked on 9/5/2026
Borrowing capacity is calculated from the maximum monthly payment you can afford, the interest rate, and the loan term. Example: with a maximum monthly payment of €1,000, a rate of 3%, and a term of 20 years, you can borrow about €180,310.91.
Explanation
This calculator answers the reverse question of our mortgage calculator: instead of starting from a borrowed amount to find the monthly payment, it starts from the maximum monthly payment you can afford to work out the amount you could borrow. Both calculations use exactly the same constant-payment formula, simply solved in the other direction. The maximum monthly payment you enter should stay consistent with your debt-to-income ratio (see our debt-to-income ratio calculator, the generally accepted threshold being 35% of net income). This result doesn't account for a down payment: the total budget for the property you can aim for is the sum of this borrowing capacity and your down payment, minus notary and application fees not financed through the loan.
Example: maximum monthly payment of €1,000, rate of 3%, 20 years
Inputs
Maximum monthly payment: €1,000/month. Annual rate: 3%. Term: 20 years (240 monthly payments).
Calculation
The monthly rate is 3% ÷ 12 = 0.25%. The formula (payment × (1 − (1 + monthly rate)⁻ⁿ) ÷ monthly rate, with n = 240 months) gives €180,310.91.
Result
With this monthly payment, rate, and term, the borrowing capacity is about €180,310.91.
Frequently asked questions
Does this borrowing capacity include a down payment?
No, this calculator only gives the amount a bank would lend for the monthly payment entered. Your total property budget equals this borrowing capacity, plus your down payment, minus notary and application fees (generally not financed by the loan itself, unless the bank agrees otherwise).
How do I choose the maximum monthly payment to enter?
A common rule of thumb is to keep loan payments below 35% of your net monthly income (the HCSF threshold in France, including borrower's insurance) — see our debt-to-income ratio calculator to check this ratio from your income. Also stay realistic about your actual residual living income, beyond simply meeting this regulatory threshold.
Why does borrowing capacity increase with a longer loan term?
Over a longer term, the same monthly payment repays a larger amount of principal, since that principal is amortized over more payments. Be careful, though: extending the term also increases the total cost of the loan (more interest paid overall), even though the amount borrowed is higher — see our mortgage calculator to visualize this trade-off.