Walk into any dispensary in America and the menu is organized around a measurement system that blends metric precision with imperial tradition, uses slang that varies by region, and assumes a baseline familiarity that new consumers simply do not have. What is an eighth? How much is a zip? Why does the guy behind the counter weigh everything in grams but sell it in fractions of ounces?

The cannabis measurement system is a legacy of decades of illicit commerce, where standardized packaging did not exist and transactions relied on shared understanding of informal units. Legal markets have inherited this system largely intact, adding lab-tested labels and childproof containers but retaining the same weight increments that have defined cannabis transactions for generations.

This guide breaks down every standard measurement, what each one looks like in practice, how pricing typically scales, and the legal purchase limits that determine how much you can buy in a single transaction.

The Fundamental Units

Cannabis is weighed in grams and sold in quantities derived from the imperial ounce. One ounce equals 28.3495 grams, but the cannabis industry rounds to 28 grams for practical purposes. Every standard cannabis measurement is either a gram amount or a fraction of this 28-gram ounce.

This metric-imperial hybrid exists because cannabis culture developed primarily in the United States (imperial system) but adopted the gram as its base unit because it provides the precision needed for small quantities. You would not buy 0.035 ounces of cannabis, but you would buy a gram.

One Gram (1g)

What it is: The smallest standard unit of cannabis flower sold in dispensaries.

What it looks like: A single gram of cannabis flower is roughly the size of a large grape or a small cherry tomato. It is a single dense nugget or two to three smaller buds. It fits comfortably on a quarter (the coin) or fills the bottom of a small pill bottle.

What you can do with it: A gram of flower will roll one medium joint (0.5 to 0.75 grams of flower per joint, with the rest being paper and filter) or fill two to three bowls in a standard pipe or one to two bowls in a bong. For a new consumer, a gram can provide two to four sessions depending on consumption method and dose.

Typical pricing: $8 to $20 at dispensaries depending on state, quality tier, and market maturity. High-end single grams (top-shelf flower, exotic cultivars) can reach $25 or more in premium markets. Budget options in competitive markets like Oregon or Colorado can be found for $5 to $8.

When to buy it: When trying a new strain, when you consume infrequently, or when budget is constrained. The per-gram price at the single-gram level is the highest you will pay — quantity discounts start at the next increment.

An Eighth (3.5g)

What it is: One-eighth of an ounce, or 3.5 grams. This is the most commonly purchased quantity in American dispensaries and the default unit for most consumers.

What it looks like: An eighth of cannabis flower fills the palm of an average adult hand when loosely piled. It is roughly the size of a kiwi fruit or a golf ball. Depending on bud structure and density, it might be three to five large nugs or a handful of smaller ones. Dense, tightly trimmed flower will look smaller by volume than airy, loosely structured flower at the same weight.

What you can do with it: An eighth provides approximately five to seven standard joints (0.5 grams each), seven to ten pipe bowls, or roughly one to two weeks of light daily use. For moderate consumers (one session per day), an eighth typically lasts five to seven days.

Typical pricing: $25 to $60, with enormous variation by market. Colorado and Oregon — mature, competitive markets with significant oversupply — commonly offer eighths at $20 to $35 for quality flower. New York and Illinois — newer markets with fewer licenses and higher operational costs — see eighths at $45 to $65 for comparable quality. Premium and exotic cultivars command $50 to $70 in most markets.

Why it dominates: The eighth occupies the sweet spot between sample size and value. It is enough to last a moderate consumer a week, small enough to not go stale before use, and priced at a point that provides a meaningful per-gram discount over single-gram purchases — typically 15% to 25% cheaper per gram.

A Quarter (7g)

What it is: One-quarter of an ounce, or 7 grams. Exactly two eighths.

What it looks like: A quarter fills a standard sandwich bag to a shallow depth or fills a small mason jar (4 oz size) about halfway. It is roughly the volume of an apple. The visual impression of a quarter is noticeably more substantial than an eighth — this is the quantity where you start to feel like you have a meaningful supply.

What you can do with it: Approximately 10 to 14 joints, 14 to 20 pipe bowls, or two to three weeks of moderate daily use. A quarter is often enough flower to last a regular consumer through a pay period.

Typical pricing: $45 to $100, with per-gram savings of 20% to 30% compared to buying two separate eighths. In competitive markets, quarters at $50 to $60 for quality flower are common. Some dispensaries offer quarter specials as loss leaders to drive foot traffic.

When to buy it: When you have settled on a strain you enjoy and want a supply that lasts more than a few days. The quarter is the most efficient balance of freshness and value for regular consumers who use cannabis three to five times per week.

A Half Ounce (14g)

What it is: One-half of an ounce, or 14 grams. Also called a “half” or “half O.”

What it looks like: A half ounce fills a standard sandwich bag with some depth, or fills a standard mason jar (8 oz) roughly halfway. Visually, it is a substantial quantity — enough to cover the bottom of a dinner plate in a thin layer.

What you can do with it: Approximately 20 to 28 joints, 28 to 40 pipe bowls, or one month of moderate daily consumption. A half ounce is a meaningful bulk purchase for personal use.

Typical pricing: $80 to $160. The per-gram discount at the half-ounce level is significant — typically 30% to 40% cheaper per gram than single-gram pricing. In oversupplied markets, half ounces of mid-tier flower can be found for $60 to $80.

When to buy it: When you are a committed daily consumer with a strain you know and like, or when you are stocking up during a sale. Freshness becomes a consideration at this quantity — cannabis flower degrades over time (losing potency and terpenes), so a half ounce should ideally be consumed within two to four weeks and stored properly (airtight, cool, dark, with humidity control).

One Ounce (28g)

What it is: The full ounce, 28 grams. Also called an “O,” a “zip” (from the ziplock bag it traditionally arrived in), or an “oz.”

What it looks like: An ounce of cannabis flower fills a standard quart-sized ziplock bag, or fills a standard mason jar (8 oz) to the brim. It is the size of a large handful — enough to visually register as a significant quantity. One ounce is typically the maximum purchase limit in legal recreational markets, and it represents a substantial personal supply.

What you can do with it: Approximately 40 to 56 joints, 56 to 80 pipe bowls, or one to two months of daily consumption for a moderate user. An ounce is also enough to make a meaningful batch of cannabutter or infused oil.

Typical pricing: $100 to $300 depending on market and quality. The ounce is where the deepest bulk discounts apply, with per-gram prices often 40% to 50% below single-gram pricing. In highly competitive markets (Oregon, Colorado, Michigan), quality ounces can be found for $80 to $120. In newer or less competitive markets, $200 to $280 is more typical for quality flower.

The ceiling for most consumers: An ounce is the standard maximum for recreational purchase in most legal states. It is more cannabis than most consumers need at one time, and proper storage becomes essential at this quantity to prevent degradation.

Larger Quantities

Quantities above one ounce are relevant primarily for medical patients with high-volume needs, commercial cultivation, and wholesale transactions. Most recreational consumers will never purchase in these quantities, and many state laws prohibit recreational possession above one ounce.

Quarter pound (QP) — 4 ounces, 112 grams. A quarter pound is a wholesale unit. In the legal commercial supply chain, this is a unit of transaction between cultivators and processors or between processors and dispensaries. Recreational consumers cannot legally purchase a quarter pound in any state. Medical patients in some states may possess larger quantities with appropriate documentation.

Half pound — 8 ounces, 224 grams. Another wholesale unit. Half-pound transactions define the mid-level commercial market.

One pound — 16 ounces, 448 grams. The standard wholesale unit for large-scale commercial cannabis. Wholesale pound prices are the industry’s benchmark for flower valuation. As of early 2026, wholesale pound prices in mature markets range from approximately $400 to $800 for outdoor-grown flower, $800 to $1,600 for greenhouse, and $1,200 to $3,000 for indoor premium flower. These prices have declined dramatically from 2021 highs, reflecting industry maturation and oversupply.

Pre-Roll and Concentrate Measurements

Pre-rolls are sold by the weight of cannabis they contain, typically 0.5 grams (half-gram pre-roll), 0.75 grams, or 1 gram. Multi-packs (such as a 5-pack of 0.5 gram pre-rolls, totaling 2.5 grams) are increasingly popular. Infused pre-rolls — rolled with flower and then coated or filled with concentrate — are sold at higher price points and may list both flower weight and concentrate weight separately.

Concentrates (wax, shatter, live resin, rosin, distillate) are sold in smaller quantities than flower because they are substantially more potent by weight. Standard concentrate quantities are:

  • 0.5 grams: Common for premium live rosin and hash rosin, typically $25 to $50.
  • 1 gram: The most common concentrate purchase size, typically $20 to $80 depending on type and market.
  • 3.5 grams (an eighth): Bulk concentrate purchase, usually at significant per-gram discount.

Vape cartridges are sold by volume (milliliters) rather than weight, with 0.5 mL and 1 mL being the standard sizes. A 1 mL cartridge contains approximately 1 gram of cannabis oil by weight, depending on density.

Edibles are sold by total THC content in milligrams rather than by weight. A package might contain 100 mg of THC distributed across 10 gummy pieces (10 mg each). The physical weight of the edible product is irrelevant for dosing purposes — only the milligram THC content matters. For a breakdown of what each milligram level actually feels like, see our THC dosing guide.

The Pricing Curve

Cannabis pricing follows a predictable bulk discount structure that rewards larger purchases. The economics are straightforward: each transaction has fixed costs (packaging, staff time, compliance tracking) that are distributed across a larger quantity, and retailers earn sufficient margin on bulk purchases even at lower per-unit prices.

The approximate per-gram cost structure in a mature, competitive legal market (mid-tier quality flower) looks roughly like this:

  • Single gram: $10 to $15 per gram
  • Eighth (3.5g): $8 to $12 per gram
  • Quarter (7g): $7 to $10 per gram
  • Half ounce (14g): $6 to $9 per gram
  • Ounce (28g): $4 to $8 per gram

These are averages across competitive markets. Premium flower commands higher prices at every increment, and budget or shake options are available well below these ranges. Taxes — which vary enormously by state and can add 15% to 40% to the shelf price — are not included in these ranges.

The practical implication is that buying by the gram is the most expensive way to purchase cannabis, and buying by the ounce is the most cost-effective. The per-gram cost drops roughly 40% to 60% between a single gram and a full ounce. For regular consumers, the math strongly favors purchasing in larger quantities — provided they consume fast enough to use the flower before significant quality degradation occurs.

Legal cannabis states impose maximum purchase limits — the most cannabis you can buy in a single transaction or possess at one time. These limits vary by state and typically differ between recreational and medical consumers.

Common recreational purchase limits (as of early 2026):

Most recreational states allow purchase of 1 ounce (28 grams) of flower per transaction. This is the standard limit in Colorado, California, Oregon, Washington, Michigan, Illinois, Arizona, New Jersey, and most other recreational states.

Some states have different limits. Alaska allows 1 ounce. Maine allows 2.5 ounces. Vermont allows 1 ounce. Montana allows 1 ounce. Connecticut allows 1.5 ounces.

Concentrate limits are separate from flower limits and are typically lower by weight because concentrates are more potent. Common concentrate limits are 5 to 8 grams per transaction.

Edible limits are expressed in total THC milligrams rather than product weight. Many states cap single-transaction edible purchases at 800 to 2,000 mg of THC.

Medical purchase limits are generally higher than recreational limits in states that maintain separate medical and recreational programs. Medical patients in many states can possess 2 to 8 ounces of flower, and some states allow even larger quantities with physician authorization.

Possession vs. purchase limits: Some states distinguish between how much you can buy in a single transaction and how much you can legally possess at home. Home possession limits are often higher than single-transaction purchase limits. Check your state’s specific regulations, as the distinctions can be legally consequential.

The Weight Check: Protecting Yourself

In the legal market, pre-packaged cannabis is typically weighed and sealed at the processing facility. Dispensary staff do not usually weigh flower in front of you unless you purchase from a deli-style (open jar) display, which some dispensaries offer.

For pre-packaged products, the label states the net weight. Regulatory compliance requires accuracy within a small tolerance (usually plus or minus 0.1 to 0.3 grams depending on the state). Most licensed products are accurately weighed because regulatory penalties for consistent underweight are severe. Our dispensary evaluation guide covers additional quality indicators to check beyond weight accuracy.

For deli-style purchases, the flower should be weighed in front of you on a calibrated scale. The scale should read to at least 0.1 gram precision, and the displayed weight should match the amount you are being charged for. It is entirely reasonable to watch the weighing process and to speak up if the weight does not match your order.

If you want to verify weights at home, a digital scale accurate to 0.01 grams is available online for $10 to $30 and is a worthwhile investment for any consumer who purchases regularly. This is not a matter of distrust — it is basic consumer diligence, no different from checking that your steak weighs what the label says.

A System That Works Despite Itself

The cannabis measurement system is, objectively, a strange hybrid. It uses metric base units within an imperial framework, relies on slang that varies by generation and geography, and was developed entirely in an unregulated market where standardization was impossible. The fact that it works — that a consumer in Portland and a consumer in Miami both understand what an eighth means — is a testament to the power of informal standardization through decades of shared practice.

Legal markets have layered regulatory precision on top of this informal system. Every product is now labeled with exact weights, batch numbers, and lab-tested potency figures. The math that consumers once had to trust (or verify with a pocket scale) is now validated by compliance infrastructure.

But the vocabulary remains unchanged. You still buy an eighth. You still ask about the price per zip. The measurement system of cannabis is one of the few aspects of the industry that has survived the transition from prohibition to regulation with its character fully intact. For definitions of other cannabis terminology you may encounter, check our glossary.