A jar of dried flower labelled "Total THC 24%" and a package of gummies labelled "10 mg THC" are describing the same molecule in two different languages. One is a concentration. The other is an absolute amount. Until you can translate between the two, the numbers on Canadian cannabis labels look contradictory — a legal jar of flower contains hundreds of milligrams of THC while a legal package of edibles is capped at ten. This guide covers the math behind THC percentages, what "Total THC" actually means under Canada's Cannabis Regulations, the typical potency ranges for each product format sold in Alberta, and why a bigger percentage is not a quality score. Strictly potency literacy — what the numbers mean, not what any product will do for you.
Percentage Is Just Milligrams Per Gram
The conversion is simpler than it looks: a THC percentage tells you how many milligrams of THC are in each gram of product, multiplied by ten.
One gram is 1,000 milligrams. If 20% of that gram is THC, that's 200 mg of THC per gram. From there, package math is straightforward multiplication:
| Total THC % | THC per gram | |---|---| | 10% | 100 mg | | 15% | 150 mg | | 20% | 200 mg | | 25% | 250 mg | | 30% | 300 mg |
So a standard 3.5 g jar of flower at 20% Total THC contains 3.5 × 200 = 700 mg of total THC. A 28-gram ounce of the same flower contains 5,600 mg. That sounds enormous next to a 10 mg edible — and the gap is real on paper — but the two numbers describe different things, which is the subject of the rest of this guide.
One important caveat on the flower math: 700 mg is what's *in the jar*, not what a person would ever absorb. When dried flower is combusted, a meaningful share of the THC is destroyed by heat or lost in smoke that's never inhaled, and not all of the THCA converts. The percentage describes the product as packaged, full stop.
THC vs Total THC: How to Read a Canadian Label
Pick up any legal product in Alberta and you'll see two THC lines, and they're often wildly different. A jar of flower might read THC: 0.8% and Total THC: 24%. Neither is a misprint.
- THC is the amount of active delta-9-THC present in the product *as it sits in the package*, before any heat is applied.
- THCA (tetrahydrocannabinolic acid) is the non-intoxicating acid form that raw cannabis mostly contains. Heat converts THCA into THC — a reaction called decarboxylation — which is what happens during combustion, vaporization, or the manufacturing of edibles and extracts.
- Total THC is the maximum THC the product can yield once that conversion fully happens. The calculation adjusts for molecular weight (THCA is a heavier molecule, so the standard conversion multiplies THCA by 0.877 before adding the existing THC).
Health Canada's packaging and labelling guide for cannabis products requires both values on the label, and its consumer-facing page on how to read and understand a cannabis product label walks through each field. The practical takeaway for comparing dried flower and pre-rolls: read the Total THC line. The plain THC line on raw flower is almost always a small number because the plant stores most of its THC as THCA.
Labels also carry the red standardized THC symbol (mandatory on anything intoxicating), an excise stamp proving the product came through the legal supply chain, a packaged-on date, and the lot number — all useful information that illicit product simply doesn't have.
Why Edibles Cap at 10 mg While a Jar of Flower Holds 700 mg
This is the question that confuses almost everyone at the counter. The answer is that Parliament and Health Canada regulate *packages*, and they set the limits differently for different consumption routes.
Under the Cannabis Regulations, edible cannabis is limited to 10 mg of total THC per package (the "immediate container"), whether that's one 10 mg chocolate or ten 1 mg gummies. Cannabis beverages fall under the same edible class and the same 10 mg-per-container cap. Cannabis extracts are treated differently: up to 1,000 mg of THC per container, with ingestible unit forms like capsules limited to 10 mg per unit. Dried flower has no per-package potency cap at all — it's limited by possession rules instead. Health Canada's guide on composition requirements for cannabis products lays out each class limit, and describes the edible cap as precautionary: edibles look and taste like ordinary food, which raises the risk of accidental consumption and of consuming more than intended.
The consumption route is the other half of the story. Inhaled THC is absorbed through the lungs and reaches the bloodstream quickly. Ingested THC is absorbed through the digestive tract and processed by the liver, which metabolizes delta-9-THC into 11-hydroxy-THC; intoxicating effects begin much more slowly than with inhalation and can persist longer. Because onset is delayed, a person can't gauge anything in the first half hour — one of the stated reasons the federal limit for food products is conservative. The result: a milligram number on an edible package and a milligram number derived from flower percentage are not interchangeable measures, even though the unit is the same.
So flower isn't "stronger" than edibles in any simple sense, and edibles aren't "weaker." They're different product classes, measured at different points, absorbed by different routes, and capped by different rules. More THC means more intoxicating potential within a format — comparisons across formats need more context than a single number.
Typical Total THC Ranges by Format
Here's where the products on Alberta shelves actually land. Ranges below describe what's commonly stocked, not regulatory limits (except where noted).
| Format | How potency is labelled | Typical range | |---|---|---| | Dried flower | Total THC % | 12–30%; most commercial flower sits 18–28% | | Pre-rolls | Total THC % | 12–30% for straight flower; infused pre-rolls run higher | | Vape cartridges | Total THC % (or mg/g) | 70–95% for distillate; resin/rosin carts often 60–85% | | Concentrates | Total THC % | 60–99%; THCA diamonds top the scale | | Edibles | mg per package | Capped at 10 mg total THC per package | | Beverages | mg per container | Capped at 10 mg per container | | Oils and capsules | mg per mL / mg per capsule | Capsules max 10 mg each; bottles up to 1,000 mg total |
A few notes on reading these ranges:
- Flower below 15% isn't "weak product" — it's often a deliberate cultivar choice, and CBD-dominant flower can carry single-digit THC by design.
- Vape cartridges show high percentages because they're made from extract with the plant material removed — concentration, not magic. A 1 g cartridge at 85% contains 850 mg of total THC dispensed across hundreds of small activations, which is why a percentage alone tells you little about any single use.
- Concentrates (shatter, wax, rosin, hash, diamonds) span the widest range. Traditional pressed hash might test 30–50%, while isolated THCA diamonds approach 99% by weight.
- Edibles and beverages never show a percentage — only milligrams. That's the format where the label number maps directly to an exact amount.
The Conversion Table: Percent to Milligrams by Package
Bookmark this section if the math ever gets slippery. Formula: grams in package × (percentage × 10) = total mg of THC.
| Product | Label | Math | Total THC in package | |---|---|---|---| | 3.5 g flower | 20% | 3.5 × 200 mg/g | 700 mg | | 3.5 g flower | 28% | 3.5 × 280 mg/g | 980 mg | | 7 g flower | 22% | 7 × 220 mg/g | 1,540 mg | | 28 g flower | 18% | 28 × 180 mg/g | 5,040 mg | | 1 g pre-roll | 25% | 1 × 250 mg/g | 250 mg | | 3 × 0.5 g pre-rolls | 30% | 1.5 × 300 mg/g | 450 mg | | 1 g vape cartridge | 85% | 1 × 850 mg/g | 850 mg | | 1 g concentrate | 92% | 1 × 920 mg/g | 920 mg | | Package of gummies | 10 mg | regulatory cap | 10 mg | | Cannabis beverage | 10 mg | regulatory cap | 10 mg |
Reading the table top to bottom makes the regulatory logic visible: inhaled formats are sold by concentration and can hold large absolute amounts; ingested formats are sold by exact milligrams and capped low.
Why THC Percentage Is Not a Quality Score
The single most common shopping mistake in legal cannabis is treating Total THC like a review score — 30% must be "better" than 22%. The number doesn't work that way, for several factual reasons:
- It's a sample measurement. The percentage comes from lab testing of a sample from the lot, and plant material is naturally variable. Two jars from the same harvest can test points apart; the label reflects the tested lot, not your specific buds.
- Moisture moves the number. THC percentage is measured by weight. Drier flower shows a higher percentage with the same THC content, simply because water weight is gone.
- THC is one compound among many. Cannabis produces dozens of cannabinoids (CBD, CBG, CBN and others, which appear on many labels) and terpenes — the aromatic compounds responsible for whether a cultivar smells like citrus, pine, diesel or pepper. None of that appears in the THC line, yet it's most of what distinguishes one cultivar from another on the shelf.
- Freshness and cure matter to the product you actually receive. The packaged-on date on every legal label tells you more about condition than a two-point THC difference does. THC also degrades over time into CBN, so an old high-percentage jar may no longer match its label.
- Chasing percentage distorts price comparisons. Dollars-per-gram-of-THC is a spreadsheet stat, not a measure of whether a product is well-grown, well-cured, or what you're actually looking for.
Percentage tells you one thing accurately: how much THC, by weight, the tested lot contained. It says nothing about craftsmanship, aroma, smoothness, or whether the product suits your purpose. Treat it like alcohol-by-volume on a bottle — relevant information, never a quality rating.
Putting It to Work in an Alberta Store
Every product Bud Mart sells comes through AGLC, Alberta's legal wholesaler and regulator, so every label follows the federal format described above — Total THC, standardized symbol, excise stamp, packaged-on date, lot number. Staff at any of our nine Alberta locations can walk you through a label line by line, whether you're comparing two jars of flower or trying to understand why a beverage lists 10 mg while the cartridge beside it lists 82%. You must be 18+ with valid ID to enter or purchase.
If you already know what you're after, the same label information appears on every product page across our Calgary menu, and same-day Toonie Delivery ($1.99) runs 9 am–10 pm across Calgary, Airdrie, Chestermere and the town of Didsbury, typically in 45–60 minutes. For deeper dives into specific formats, see our guides to edibles dosing labels, pre-rolls, and the vape-versus-flower comparison.
FAQ: THC Percentages and Milligrams
How many milligrams of THC are in 3.5 grams of 20% flower?
700 mg of total THC. The math: 20% of one gram (1,000 mg) is 200 mg of THC per gram, and 3.5 g × 200 mg = 700 mg. That figure describes the THC contained in the package as tested — when flower is combusted, a substantial portion of that THC is lost to heat and sidestream smoke rather than absorbed.
What's the difference between THC and Total THC on a Canadian label?
THC is the active delta-9-THC in the product as packaged; Total THC is the maximum THC available after heat converts the plant's THCA (the non-intoxicating acid form) into THC. Raw flower stores most of its THC as THCA, which is why a label can read "THC 0.8% / Total THC 24%." For comparing dried flower or pre-rolls, Total THC is the number to use — a requirement detailed in Health Canada's labelling rules.
Why are edibles limited to 10 mg of THC per package in Canada?
The Cannabis Regulations cap edible cannabis at 10 mg of total THC per immediate container as a precaution: edibles resemble ordinary food, intoxicating effects begin slowly after ingestion, and both factors raise the risk of accidental or excess consumption. Cannabis extracts are capped separately at 1,000 mg per container, and dried flower has no per-package potency cap.
Is a higher THC percentage better quality?
No. The percentage is a lab measurement of THC concentration by weight in a tested sample — it isn't a score for how well the product was grown, cured or made. Moisture content shifts the number, lots vary naturally, and the compounds that give a cultivar its aroma and character (terpenes and minor cannabinoids) aren't reflected in the THC line at all. More THC means more intoxicating potential, nothing more.
Why do vape cartridges show 80–90% THC when flower tops out around 30%?
Because cartridges contain extract, not plant material. Removing the plant matter concentrates the cannabinoids, so the percentage rises even though the total amount in a 1 g cartridge (roughly 800–900 mg) is dispensed across hundreds of small activations. The percentage describes concentration, not how much THC any single use delivers.
Does 10 mg of THC in an edible equal 10 mg of THC in flower?
The milligrams are chemically identical, but the numbers aren't interchangeable in practice. An edible's 10 mg is ingested, absorbed through the digestive tract and metabolized by the liver into 11-hydroxy-THC, with slow onset; flower's THC is inhaled, with rapid absorption and significant losses to combustion. Same unit, different measurement points and different routes — which is exactly why federal rules cap the two formats differently.
How much cannabis can I legally carry in public in Alberta?
The federal Cannabis Act limits adults to 30 grams of dried cannabis, or the public-possession equivalent, and its schedules set the conversion: one gram of dried cannabis equals roughly 15 g of edibles, 70 g of beverages, or 0.25 g of concentrates. Legal retailers apply the same equivalency math at checkout, which is why a cart of high-equivalency products can hit the limit faster than its shelf size suggests.
Sources
- Government of Canada — Cannabis Act, S.C. 2018, c. 16
- Government of Canada — Cannabis Regulations, SOR/2018-144
- Health Canada — Packaging and labelling guide for cannabis products
- Health Canada — How to read and understand a cannabis product label
- Health Canada — Guide on composition requirements for cannabis products
- Alberta Gaming, Liquor and Cannabis — Cannabis in Alberta
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*Last updated: June 10, 2026. Product class limits and labelling rules come from the federal Cannabis Act and Cannabis Regulations and can change; verify current requirements with the official sources above. This page is factual potency and label literacy for adults 18+ in Alberta — nothing here is medical advice, and no statement about THC content is a claim about what any product will do.*
Information only. This content is for informational purposes and does not constitute medical advice. Cannabis products are for adults 18+ with valid ID. Consult a healthcare professional for medical questions.