Mortgage affordability calculator
Model mortgage affordability with maximum monthly payment, loan amount, purchase budget, interest cost and rate scenarios.
- 100% local
- Instant
- Free
- No account
- Works offline
Your borrowing capacity
Change your income, debts and loan assumptions to update the affordability estimate instantly.
Monthly budget breakdown
—Maximum debt ratio
New mortgage—
Existing debts—
Other housing costs—
Income left—
Rate and term sensitivity
| Rate | Term | Payment | Borrowing capacity | Purchase budget |
|---|
Why use this tool?
This calculator estimates an affordable home budget from monthly income, existing debts, down payment, interest rate, term and an adjustable debt-ratio ceiling. It is a planning estimate rather than a loan approval.
100% local and secure
Your data stays on your device and is never sent to our servers.
Smart processing
Calculate and compare financial scenarios with clear indicators and explicit formulas.
Supported formats
Amounts, rates, terms and financial assumptions depending on the calculator.
Save time
Get a clean, ready-to-use result in seconds without installing software or configuring a complex workflow.
Fonctionnement
How does this tool work?
The monthly debt ceiling is calculated by applying your selected debt ratio to household income.
Existing debts and recurring housing costs are deducted to determine the payment available for a new mortgage.
The loan amount is derived from that payment, the annual interest rate and the term using a fixed-payment amortization formula.
The down payment is added to the loan amount and the sensitivity table shows the effect of different rates and terms.
Use cases
Plan a home purchase
Estimate a search budget before viewing properties or meeting a broker.
Compare loan terms
See how term length affects borrowing capacity and total interest.
Stress-test interest rates
Measure how a higher or lower rate changes the amount you can borrow.
Guide
How to use this tool
- 1
Enter household income
Use a consistent monthly income basis.
- 2
Add existing commitments
Include current debt payments and recurring housing costs.
- 3
Set financing assumptions
Enter down payment, interest rate, term and target debt ratio.
- 4
Compare scenarios
Review purchase budget, loan amount, payment and sensitivity results.
Tips and best practices
- Test a slightly higher rate to keep a safety margin.
- Maximum borrowing capacity is not always a comfortable budget; preserve enough residual income.
- If the down payment must also cover closing costs or renovation, do not add all of it to the property price.
Frequently asked questions
Is this a mortgage approval?
No. A lender may use different income, expense, insurance and underwriting rules.
Why are existing debts deducted?
They already consume part of the monthly repayment capacity.
Does a larger down payment increase the maximum payment?
No. It increases the purchase budget while the payment ceiling still comes from income and debt assumptions.
What belongs in other housing costs?
Insurance, recurring property charges, monthly taxes or other housing costs you want to reserve.
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