Mortgage Qualifier Calculator

Conventional A-lender limits are 39% GDS and 44% TDS. GDS (Gross Debt Service) is your mortgage payment plus property tax, heat, and 50% of condo fees, divided by gross household income. TDS (Total Debt Service) adds every other monthly debt payment — car loans, credit card minimums, lines of credit, student loans, support payments. Both are measured at the stress-test rate, not your contract rate. Some lenders stretch to 42/50 on strong credit, and B-lenders regularly approve well past those caps at higher pricing.

Under OSFI Guideline B-20 you must qualify at the greater of your contract rate plus 2 percentage points, or 5.25% — whichever is higher. At a 4.29% contract rate you are tested at 6.29%. At a 3.00% contract rate you are tested at 5.25%, because the floor binds. This applies to all federally regulated lenders. The test does not change what you pay; it changes what you are allowed to borrow.

Five percent on the first $500,000, ten percent on the portion between $500,000 and $1,500,000, and twenty percent at $1,500,000 or above. On an $850,000 home the minimum is $60,000 — $25,000 on the first $500,000 plus $35,000 on the remaining $350,000. Mortgage default insurance is unavailable at or above $1,500,000, which is why 20% becomes a hard floor rather than a preference.

Lenders include 50% of a condo maintenance fee in GDS and TDS because a portion of the fee covers utilities, amenities and reserve fund contributions rather than pure shelter cost. A calculator that includes 100% of the fee will understate what you qualify for, sometimes by tens of thousands of dollars in purchase price. This calculator applies the 50% treatment.

Yes. With less than 20% down, default insurance is mandatory and the premium is added to the loan rather than paid up front. Premium rates by loan-to-value: 2.80% at 15–19.99% down, 3.10% at 10–14.99%, and 4.00% at 5–9.99%. Because the premium is financed, it increases the payment used in your GDS and TDS tests — a detail most calculators skip.

The Interest Act (Canada) requires regulated lenders to compound residential mortgage interest semi-annually, twice per year. US mortgages compound monthly. Using the American formula overstates a Canadian payment by roughly $20 to $40 per month on a typical file. Every figure on this page uses the Canadian semi-annual formula.

Four levers, in rough order of impact. Reduce other debt — paying off a $500 car payment frees roughly $110,000 of purchase price at typical ratios. Increase the down payment, which cuts both the loan and the insurance premium. Extend amortization, since 30 years lowers the qualifying payment against 25. Or add a co-borrower whose income counts and whose debts also count. A broker can also place the file with a lender using wider ratios.

No. This tests the debt-service ratios, which is the arithmetic gate. Approval also depends on credit score and history, income verification and how it is documented, employment tenure and type, the property itself and its appraisal, and the specific lender policy. Self-employed income in particular is treated very differently across lenders. Treat a pass here as "the math works," not as a pre-approval.