Borrowing Power Calculator
Work backwards from a monthly payment you are comfortable with to the loan it supports, and see the total interest that loan would cost.
Are you a real estate agent or broker? Put this calculator on your own agent page, beside your listings, so the buyer who ran the numbers can message you in one tap. Create free agent page →
Most buyers pick a property, then find out what it costs each month. Working the other way round is far more useful: decide the payment you are genuinely comfortable with, and see what loan that supports at today rates.
The number this produces is not the same as what a lender will offer. Lenders assess against gross income and stress-test at a higher rate, so their maximum is frequently well above a payment you would actually enjoy making for twenty-five years.
The formula
This is the mortgage payment formula rearranged for the amount: loan = payment × (1 − (1 + i)^−n) ÷ i, where i is the monthly rate and n the number of months. The property price you can reach is that loan plus your deposit.
Worked example
A payment of 1,500 at 6.5% over 25 years supports a loan of about 222,150. With a 60,000 deposit that reaches a property price near 282,150. Over the term you would repay 450,000 in total, of which roughly 227,800 is interest — more than the loan itself.
Leave room for everything else
The payment is not the cost of owning. Property tax, insurance, maintenance and any service charge are on top, and maintenance in particular is lumpy rather than monthly. A payment that uses every spare unit of income leaves nothing for the boiler.
Put your number on the page that answers the question
Buyers remember whoever gave them the answer. A property page of your own carries this calculator, your listings and a WhatsApp button, so the next question comes to you.
Create your free property pageFrequently asked questions
Why is a lender offer different from this?
Lenders assess gross income against affordability rules and stress-test the payment at a rate above the one you are offered. Their maximum answers whether you can survive a rate rise, not whether the payment is comfortable today.
Should I borrow the maximum I can?
Rarely. Borrowing to the limit leaves no capacity for a rate rise, a repair or a change of job, and those are the ordinary events that turn a stretched mortgage into a forced sale.
Does a longer term let me borrow more?
Yes, and it costs considerably more interest. Extending from twenty-five to thirty-five years raises the loan a given payment supports, but you pay for that increase for ten extra years.
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