Guides and explainers
Some rules genuinely need more than a calculator. These guides cover the ones where the answer depends on which province you are in, which programme you are applying to, or which year you are filing for.
GST, HST, PST and QST rates by province
The current rate for all thirteen provinces and territories, and why Canada runs three different systems at once.
How to remove HST from a total
Why you divide rather than subtract, what the error costs, and the numbers for each HST province.
Express Entry no longer gives points for a job offer
IRCC deleted arranged employment points in March 2025. Most calculators still award them.
Why Toronto buyers pay land transfer tax twice
One provincial tax, one municipal tax, and the boundary that costs $14,475 to cross.
Why Canadian mortgages compound semi-annually
A single clause in the Interest Act is why a 5% Canadian mortgage is not a 5% American one.
The rule of 65, and how two years of age changes everything
Why a 12-year marriage ending at 53 gets indefinite support and one ending at 50 does not.
The BC first-time buyer exemption has a $25,000 cliff
Full relief to $835,000, nothing at $860,000, and an effective marginal rate that will surprise you.
Why 'diameter minus pitch' actually works
The shop shortcut is the real formula at 77% engagement — and there are two constants people confuse.
Why your property tax rose when your assessment fell
Your bill depends on how your assessment moved relative to everyone else's, not on the number itself.
Converting a percentage to a GPA in Canada
There is no national scale. What your percentage converts to depends entirely on who is asking.
BC PNP or Alberta PNP: which grid suits your profile
Two provincial programmes, two very different scoring philosophies — and wage matters in only one.
The RRSP withholding trap: one cent can cost you hundreds
The rate applies to the whole withdrawal, not the slice above the bracket. Crossing $5,000 by a cent costs real money.
Quebec's QST is not charged on the GST
It was, until 2013. A lot of published guidance and more than a few point-of-sale systems never caught up.
Ordering concrete in Canada: metres, yards and the short-load fee
Ready-mix is sold by the cubic metre, landscaping by the yard, and running short costs more than over-ordering.
Why two conductors get less conduit fill than three
53%, then 31%, then 40%. The order is not a typo, and the reason is geometry rather than heat.
Why every bike tire pressure calculator gives a different answer
The research everyone cites was published as a chart, not an equation. Everything since is a fitted curve.
IPF GL points have replaced Wilks — what changed
The federation moved to a new relative-scoring formula in 2020. Wilks scores are still quoted everywhere.
Balloon payments on equipment finance: what they really cost
A residual cuts the monthly payment by deferring principal — and charges interest on it the whole way.
Canada sells bras in two different sizing systems
Cup letters agree to a D and then split. The same body is a 34DDD in one brand and a 34E in another.
Why a half circle skirt needs a bigger waist hole, not a smaller one
Less circle means more radius. It feels backwards, and the arithmetic is unavoidable.
How the OAS clawback actually works
It is a 15% recovery tax on income above a threshold — not a cut to your pension, and not a marginal rate you can ignore.
The Disability Tax Credit is a gateway, not just a credit
Approval unlocks the RDSP, the Canada Disability Benefit and up to ten years of retroactive claims.
Ontario Works and ODSP are not the same programme
Different eligibility tests, different rates, and very different treatment of earned income.
What probate actually costs in Ontario
The estate administration tax is the small part. The delay and the paperwork are the expensive parts.
Corrected age: why your preemie is two ages at once
Chronological age counts from birth. Corrected age counts from the due date — and it is the one milestones are measured against.
Why your training paces come from one race result
A single recent race estimates your current fitness, and every training pace follows from it.
How EI benefits are actually calculated
55% of average insurable weekly earnings, capped — and the number of best weeks depends on where you live.
How language test scores convert to CLB levels
IELTS, CELPIP, TEF and TCF all map onto one scale — and your weakest ability is what counts.
Caffeine's half-life is why your afternoon coffee is still working at bedtime
Around five hours on average — so a quarter of a 3pm coffee is still circulating at 1am.
Punnett squares predict ratios, not outcomes
A 3:1 ratio does not mean three of your four offspring. Each one is an independent roll.
The arithmetic of listening at 1.5x
Speed and time saved are not proportional. Going from 1x to 1.5x saves far more than 1.5x to 2x.