Canadian mortgage calculators
Five tools for the decisions you'll actually face when getting or renewing a Canadian mortgage. The math behind each one is implemented as pure functions with unit tests, so the calculator and our test suite use the same code.
Mortgage Payment Calculator
Estimate your payment, total interest, and CMHC premium with the Canadian semi-annual compounding convention.
- Inputs
- Home price, down payment %, rate, amortization, frequency.
- Output
- Per-payment dollars, CMHC premium, total interest, total cost. Includes a balance + cumulative-interest line chart.
Mortgage Affordability Calculator
How much mortgage you'd qualify for under GDS/TDS ratios and the federal stress test, plus a rate-sensitivity bar chart.
- Inputs
- Income, debts, property tax, heat, condo fees, down payment, rate, amortization.
- Output
- Maximum purchase price + binding constraint (GDS or TDS), with a chart of how the max moves at ±2pp around your rate.
Fixed vs Variable Mortgage Calculator
Model the break-even between locking in a fixed rate and riding a variable through hold/cuts/hike scenarios.
- Inputs
- Loan amount, amortization, term length, fixed rate, variable rate, projected variable-rate change, pace.
- Output
- Total interest under each path, winner, and a side-by-side cumulative-interest chart over the term.
Mortgage Break Penalty Calculator
Estimate the 3 months' interest or IRD penalty before breaking — and net it against the interest you'd save by refinancing.
- Inputs
- Balance, current rate, months remaining, mortgage type, today's rate, posted-rate spread (Big 6 only).
- Output
- Break/Stay/Marginal verdict with the net dollar impact, plus penalty and savings breakdowns.
Closing Costs Calculator
Province-aware land transfer tax, municipal LTT (Toronto/Halifax/Montreal), first-time buyer rebates, and standard closing fees.
- Inputs
- Purchase price, province, city, first-time buyer flag, new-build flag, optional fee overrides.
- Output
- Net LTT (provincial − municipal − rebate), legal/title/inspection, total closing costs.