Mortgage Qualifier Calculator

Find out exactly how much home you qualify for — Canada (GDS/TDS + B-20) or USA (28/36 rule).

GDS/TDS · B-20 stress test · 28/36 DTI rule · Canada & USA

Qualification Details

Income

$
$

Mortgage Terms

%
$

Monthly Housing Costs

$
$

Monthly Debt Obligations

$
$
$

Qualifies — 28/36 Rule Pass

Maximum Home Budget

$358,126

Max Mortgage

$278,126

Est. Monthly P&I

$1,666.67

Front-End

28.0%

limit 28%

Back-End

28.0%

limit 36%

Understand exactly what drives your qualification.

Borrowing Capacity

Qualification Snapshot

Maximum Home Price

$358,126

$278,126max mortgage
Max Mortgage
$278,126
Down Payment
$80,000
Est. Monthly P&I
$1,666.67

Qualifying Ratios at Maximum Budget

Front-end & back-end ratios at your estimated maximum purchase price (28/36 rule)

Front-End Ratio

28%/ 28%At estimated limit

Includes: Principal & Interest · Property Tax · Heating

Back-End Ratio

28%/ 36%Within limit

Includes: All front-end components · Car / Vehicle Payments · Credit Card Minimums · Other Monthly Debts

Ratios are calculated at your maximum qualifying price. At a lower purchase price, your ratios improve proportionally.

FinCalc Smart AI Qualifier Analysis

Qualification Verdict

Qualifies

28/36 Rule — both ratios pass

Front-end 28.0% / 28% — At estimated limitBack-end 28.0% / 36% — Within limit

Good news — you qualify for this purchase.

Your income and debt profile meet 28/36 rule front-end and back-end thresholds. You have borrowing room at your current figures.

Smart Optimization Found

Top Lever

$50,100

potential extra qualifying budget

Add $10,000/yr household income

Additional qualifying income can expand borrowing capacity by increasing available front-end/back-end room.

Estimate based on current inputs — actual lender results may vary.

What's Limiting You

Income & housing are balanced

No single factor is constraining you. Both front-end (28.0%) and back-end (28.0%) clear lender limits.

Qualifying Power

+$16,688 per $100.00/mo debt cut

No current debts — full qualifying power applied to your income.

Rate Sensitivity

+1% rate typically ≈ 8–10% less qualifying power

Illustrative industry range at 5.25% — each 1% rate increase meaningfully reduces qualifying power. A fixed rate locks in your qualification basis.

Income & Capacity Breakdown

Monthly Income

$7,916.67

Monthly Debts

None

Max P&I Capacity

$1,666.67

Back-end Headroom

8.0pp left

Disclaimer: This analysis is for illustrative purposes only and does not constitute financial, tax, or mortgage advice. Individual results will vary based on lender terms, credit profile, and market conditions. Consult a licensed mortgage professional before making financial decisions.

How It Works

Canada — GDS & TDS Ratios with B-20 Stress Test

Canadian lenders use two debt-service ratios to qualify borrowers. The stress test requires qualifying at the higher of your contract rate + 2% or 5.25% — this calculator applies it automatically.

GDS = (P&I + Property Tax + Heating) / Gross Monthly Income × 100 TDS = (GDS components + All Other Debts) / Gross Monthly Income × 100 Stress Rate = max(Contract Rate + 2%, 5.25%)

This calculator uses a 39% GDS and 44% TDS planning limit for Canadian scenarios. For insured mortgages (<20% down), these match CMHC’s published qualification ratios. For uninsured mortgages (20%+ down), actual lender underwriting may differ, so the same 39%/44% is applied here as a conservative planning estimate rather than a guaranteed limit. Semi-annual compounding applies per the Canadian Interest Act.

USA — 28/36 Rule (Front-End / Back-End)

US lenders evaluate two ratios using the contract rate directly — there is no mandatory stress test. Monthly compounding applies.

Front-End = (P&I + Tax + Insurance) / Gross Monthly Income × 100 ≤ 28% Back-End = (Housing + All Other Debts) / Gross Monthly Income × 100 ≤ 36%

Where P&I is the principal and interest payment at the contract rate with monthly compounding. Per HUD Handbook 4000.1, FHA loans allow up to 31% / 43% (higher with compensating factors); per VA guidance, VA loans have no hard DTI ceiling, but ratios above 41% back-end require stronger residual income.

Inverse Mortgage Formula — How Maximum Mortgage Is Derived

To find the maximum mortgage, the calculator first determines the largest monthly P&I payment your income and debts allow, then reverses the amortization formula to solve for principal:

Max Monthly P&I = (Income × Ratio Limit) − Tax − Heating − Other Debts Max Mortgage = Max P&I × [(1 − (1 + r)^−n) / r] r = monthly rate · n = amortization months

In Canada, the stress-test rate is used to compute Max P&I (conservative qualification), then the actual contract rate is applied in the final formula to determine the mortgage principal you can carry. This mirrors what federally regulated lenders do in practice.

Canada vs USA — Quick Comparison

FeatureCanadaUSA
Housing ratioGDS ≤ 39%Front-end ≤ 28%
Total debt ratioTDS ≤ 44%Back-end ≤ 36%
Stress testYes — rate + 2% or 5.25%No mandatory test
CompoundingSemi-annual (Interest Act)Monthly
Mortgage insuranceCMHC required <20% downPMI required <20% down

Frequently Asked Questions

This calculator is for illustrative and informational purposes only. Results are estimates and may not reflect actual mortgage terms. Individual results will vary based on lender terms, credit profile, amortization period, and prevailing market conditions. This does not constitute financial, tax, or legal advice. Consult a licensed mortgage professional or qualified financial advisor before making any financial decisions.