This calculator uses Canada's official GDS and TDS ratio limits to determine how much you can borrow. It applies the stress test qualifying rate — the higher of your contract rate + 2% or 5.25% — exactly the way lenders do.
Uses Canada's GDS/TDS stress test rules
Enter your annual gross household income — combine all income sources if you have a co-borrower. Add your monthly debt payments (car loans, credit card minimums, student loans — anything that shows on your credit bureau). Enter your available down payment, your estimated annual property tax (use $4,000–$6,000 if you're not sure), and your estimated monthly heating cost (typically $100–$200).
The calculator runs instantly as you adjust the inputs.
The Max Purchase Price is the highest home price you can qualify for under both the GDS and TDS limits simultaneously. The Max Mortgage is that purchase price minus your down payment. The Qualifying Rate shown is the stress test rate your lender must use — not your actual rate.
The GDS ratio (Gross Debt Service) measures your housing costs alone against your income. The maximum for insured mortgages is 39%. The TDS ratio (Total Debt Service) adds all your other debts. The maximum is 44%. The bar charts show where you sit relative to these limits — green means you have room, red means you're at the limit.
If the max purchase price is lower than expected, the most effective levers are: increasing your down payment (which reduces the mortgage needed), paying down existing debts before applying (which improves TDS), or adding a co-borrower's income. Even small changes to these inputs can meaningfully shift your maximum purchase price.
Note that this calculator shows the maximum you qualify for — not necessarily what you should spend. Lenders approve the maximum; financial planners recommend staying well below it.
The Gross Debt Service (GDS) ratio is your total monthly housing costs (mortgage payment, property tax, heating, and 50% of condo fees) divided by your gross monthly income. The maximum allowed for insured mortgages is 39%.
The Total Debt Service (TDS) ratio adds all other monthly debt payments (car loans, credit cards, student loans) to your housing costs and divides by gross income. The maximum is 44% for insured mortgages.
The OSFI stress test requires lenders to qualify you at the higher of your contract rate plus 2%, or 5.25%. This means you need to qualify at a higher rate than you'll actually pay, to ensure you can handle future rate increases.
Increase your down payment, reduce existing debts before applying, increase your income (or add a co-borrower), or choose a longer amortization period. Each of these improves your GDS/TDS ratios.
Explore current rates from 16+ Canadian lenders, or read our guides to understand your options.