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Finance & LoansGenerated accuracy model review: 2026-05-06

Canadian Mortgage accuracy and testing

This page documents how Calwarden builds trust for this calculator: source notes, regression-style default tests, limitations, assumptions, unit handling, rounding, and visible change history.

Formula source

  • 1. **Effective Annual Rate** = (1 + Rate/2)^2 - 1. 2. **Effective Rate per Period** is derived from the Effective Annual Rate. 3. **Accelerated Bi-Weekly**: Takes the monthly payment, divides by 2, and pays that every 2 weeks. This results in 26 full payments (equivalent to 13 monthly payments) per year.

Test cases

Default input regression check

Generated from the checked-in default inputs and calculate function.

Inputs

  • Mortgage Amount: $400,000
  • Interest Rate: 5.5%
  • Amortization: 25 Years
  • Payment Frequency: Monthly

Expected outputs

  • Estimated Mortgage Payment: $2,441.57
  • Effective Annual Rate: 5.58%

Known limitations

  • Does not calculate CMHC insurance premiums automatically. You should add the premium to the Mortgage Amount if applicable.

Assumptions

  • Inputs are interpreted exactly as entered in the calculator form.
  • The calculation runs locally in the browser using the current checked-in calculator definition.

Unit handling

  • Mortgage Amount accepts values in $.
  • Interest Rate accepts values in %.
  • Amortization accepts values in Years.
  • Payment Frequency accepts one of the configured options.
  • Estimated Mortgage Payment is displayed as currency.
  • Effective Annual Rate is displayed as a percentage.

Rounding rules

  • Number displays use up to 2 decimal places in the calculator UI.
  • Currency outputs are displayed with standard US dollar formatting.
  • Percent outputs are displayed with two decimal places.

Version history

1.0.0 - 2026-05-06

Generated accuracy and testing page from the current canadian-mortgage-calculator calculator definition.

Change log

2026-05-06

Published default regression test documentation and metadata fallbacks for Canadian Mortgage.

Calculator transparency

Accuracy pages are generated from checked-in calculator definitions and can be upgraded with curated review metadata over time.

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