Cannabis product labels pack more information than most consumers realize — and most of it matters. Whether you’re buying flower, a vape cartridge, or an edible, knowing what you’re looking at can be the difference between a product that works for you and one that doesn’t.
The Short Answer
A cannabis label should tell you: cannabinoid percentages (THC and CBD), the product weight or volume, the producer name, a batch or lot number for traceability, and any required state warnings. Beyond compliance basics, quality labels also include terpene profiles, harvest or production dates, and third-party lab test results.
THC and CBD Percentages
The most prominent numbers on any cannabis label are THC and CBD percentages. For flower, this represents the proportion by dry weight — a product labeled 22% THC means roughly 220mg of THC per gram. For concentrates and vapes, the percentage applies to the total extract weight.
What the percentage doesn’t tell you: potency alone doesn’t predict effect. Terpene composition plays a significant role in how a strain’s effects are experienced — two products with identical THC percentages can produce noticeably different experiences based on their terpene profiles.
Total Cannabinoids vs. Active Cannabinoids
Some labels distinguish between THCA (the non-psychoactive precursor found in raw flower) and THC (the activated form). When flower is combusted or vaporized, THCA converts to THC. Labels that show only “THC” may already account for this conversion; labels showing “THCA” and “THC” separately are giving you more precise information about the raw product.
A useful formula: multiply the THCA percentage by 0.877 and add the THC percentage to get the approximate activated THC after decarboxylation.
Batch Number and Lab Testing
Every regulated cannabis product should carry a batch or lot number tied to a certificate of analysis (COA) from a licensed third-party testing lab. This document covers potency verification, pesticide screening, heavy metals, residual solvents (for concentrates), and microbiological contaminants.
If a QR code is present on the label, it typically links directly to that batch’s COA. Using it before purchase is standard practice among experienced consumers. If no testing information is available or findable, that’s a meaningful signal about the producer’s transparency.
Net Weight and Serving Size
For edibles, the label must show both total THC content and per-serving THC content. In most regulated states, a single serving is capped at 10mg THC. A 100mg edible package divided into 10 pieces has 10mg per piece — straightforward, but worth double-checking since packaging designs sometimes obscure this.
For flower and pre-rolls, net weight is listed in grams. The difference between 0.5g and 0.7g pre-rolls is meaningful at scale — a habit of checking net weight prevents paying a premium price for a lighter product.
Terpene Profiles
Premium producers increasingly include terpene data on labels or COAs. Common terpenes include myrcene (earthy, relaxing), limonene (citrus, uplifting), caryophyllene (spicy, anti-inflammatory properties), and pinene (pine, alertness). If a producer lists dominant terpenes, this is more actionable information for predicting experience than THC percentage alone.
Production and Expiry Dates
Not all states require expiry dates, but responsible producers include either a packaged-on date or a best-by date. For flower, freshness matters: cannabis begins degrading within months of harvest if stored improperly. For vape cartridges and edibles, checking the production date helps avoid products that have been sitting on shelves past their optimal window.
State-Required Warnings
Labels in regulated states carry mandated warnings — typically about not operating machinery, keeping products away from children, and risks during pregnancy. These are compliance requirements and vary by state. Their presence confirms the product went through the regulated supply chain; their absence on a purchased product is worth noting.
What’s Not on the Label
Labels won’t tell you how a product will affect you personally — individual tolerance, consumption method, and biological factors all influence the experience. They also won’t tell you the price per milligram of THC, which is one of the most useful metrics for evaluating value across product categories. For that kind of cross-product price analysis, external data sources that aggregate and index cannabis pricing provide more useful benchmarks than any individual label.
Retailers that publish real-time pricing data across multiple products and merchants make it possible to compare cost per mg of THC — a metric the label itself never shows you. The Cannabis Price Index on CannabisDealsUS tracks this weekly across major online retailers.
Browse Cannabis Price Index at CannabisDealsUS.