A calculator is only as good as its numbers. Here’s where ours come from, how they get into the tools and what we do when we can’t confirm one. Everything on this page applies to the 2026 tax year.
Where do our numbers come from?
From whoever sets the rule. Federal income tax, Canada Pension Plan limits, Employment Insurance and the GST/HST rules come from the Canada Revenue Agency and Service Canada. Quebec income tax, the Quebec Pension Plan and QST come from Revenu Québec. Provincial tax brackets, credits, land transfer tax, probate fees and minimum wages come from each province or territory. Mortgage rules follow the federal lending guidelines and the published tables of the mortgage insurers.
Each figure in our data files carries the address of the page it came from and the date we read it. When the source is a table inside a PDF, we note the page. Other calculators are never a source, and that’s a firm rule.
How does a figure reach the screen?
Small scripts turn the data files into code, so nobody retypes a figure by hand. Your browser runs that code. When a rate changes, we change one data file, and every tool and every text that uses it follows.
Automated tests cover every calculator. They use worked examples: the CRA payroll tables, the official mortgage insurance premium grid, the published land transfer tax schedules. A test fails if a result moves by even a cent, so a data change can’t slip through unnoticed.
What happens when a figure is unclear?
Sometimes a source says nothing, or two official pages disagree. Then we go with the more careful reading. The page says so, and the result is labelled an estimate, since a confident number built on a guess would do you no favours. If a page rests on a figure we couldn’t confirm, it names that figure, so you know what to check yourself.
We keep a list of these open points and go through it at every update. Once the government publishes a clear answer, the note comes off, and the tool changes if it has to.
When do we review the rates?
- January: new federal and provincial brackets, credits, CPP and EI limits, and the new-year benefit amounts.
- July: benefit changes that start in July, such as the Canada Child Benefit and the GST/HST credit, and mid-year provincial changes.
- When announced: budget measures, minimum wage changes and new mortgage rules once they take effect.
The date at the bottom of each calculator is the day the page was last checked against its sources. It isn’t the day the page first went up.
How far can you trust an estimate?
Far enough to plan with. Our tools use the standard case, so they can’t see your other income, your carry-forward amounts, your employer’s payroll set-up or every credit you might claim. That’s why each page lists what it counts and what it leaves out. When you file or sign something, use the official figure from the CRA, Revenu Québec, your lender or your employer.
Found a figure that looks wrong? Tell us on the contact page, and see how we handle it on the editorial team page. Changes we have already made are listed on the updates page. Every tool is listed on the calculators page.