Quick answer: Cannabis flower is often sold in a mix of metric and imperial terms. A gram is the smallest common unit. An eighth is 3.5 grams. A quarter ounce is 7 grams. A half ounce is 14 grams. An ounce is about 28 grams. In Colorado, adults 21 and older can buy up to one ounce of retail flower, or its equivalent in other products, in a single transaction from a licensed store.
Dispensary menus use shorthand that can look confusing the first few times. Eighth, quarter, half, and ounce are fractions of an ounce, while the scale itself usually measures grams. Once the conversions are clear, labels and package sizes are easier to read.
How many grams are in an eighth, a quarter, and an ounce?
Cannabis retail culture still leans on ounce fractions even though products are weighed in grams. An ounce of flower is commonly treated as 28 grams for menu math. From that baseline, an eighth of an ounce is 3.5 grams, a quarter ounce is 7 grams (two eighths), a half ounce is 14 grams, and a full ounce is 28 grams.
Those numbers are rounded for everyday use. An exact avoirdupois ounce is 28.3495 grams, and retailers typically package to the gram amounts above. If a package lists a net weight, that printed weight is what matters for that product.
Why menus mix grams and ounce fractions
The mix is historical. Older informal markets talked in ounces and fractions of an ounce. Licensed markets kept those names because customers already knew them, while state rules and packaging require metric net weights. So a jar may say "eighth" on the shelf talker and "3.5 g" on the label.
Thinking in grams helps when reading package sizes, a scale, or how concentrates and edibles convert under state equivalency rules. Thinking in eighths and quarters helps when you are reading common menu language.
What do shake, popcorn, and full buds mean?
Weight terms describe how much flower is in the package. Other labels describe the form of that flower.
Shake usually means small loose pieces that break off buds during handling and trimming. Popcorn usually means smaller nugs that grew lower on the plant. Full buds are larger trimmed flowers. All three can come from the same cultivar. They differ mainly in size and appearance, not in the unit of weight. A quarter ounce of shake and a quarter ounce of full buds should both weigh about 7 grams if the package is accurate.
Form labels are descriptive, not a guarantee of quality by themselves. Look at harvest date, storage condition, aroma, and lab results when those details are available.
How Colorado purchase and possession limits use weight
Colorado law treats retail flower in ounce terms. Adults 21 and older may buy up to one ounce of retail flower, or its equivalent in concentrate or infused product, in a single transaction from a licensed retail store. A single transaction includes multiple purchases from the same store on the same business day when they would push the customer over the limit.
State equivalency rules convert other products into that one-ounce flower limit. One ounce of flower equals eight grams of concentrate. One ounce of flower also equals 80 ten-milligram servings of THC in retail marijuana product. Non-edible, non-psychoactive topicals are treated differently under the rules.
Possession language on state consumer pages often says adults 21 and older may possess up to two ounces. Purchase limits and possession limits are related but not the same sentence. For current wording, see Colorado's page on laws about cannabis use and the state's retail sales quantity rules.
Cannabis remains illegal under federal law. It cannot legally leave Colorado, and use on federal land is illegal. Local governments can also set stricter rules than the state baseline.
Keeping larger amounts of flower in good condition
A larger package stays useful only if the flower remains fresh and secure. Colorado's dry air can pull moisture out of flower quickly, which can make it harsh and less aromatic.
Move flower into an airtight container when you open the retail packaging, and keep it cool, dark, and away from children and pets. Colorado publishes safe storage guidance for keeping cannabis locked up and out of reach. Child-resistant packaging from the store is a starting point, not the whole storage plan.
Responsible use notes
Public consumption is illegal in Colorado. Private property with the owner's permission is the usual legal setting, and property owners can ban cannabis even at home or in hotels. Do not drive after using cannabis. This article explains terminology and legal weight limits. It is not medical advice, and it does not recommend how much anyone should consume.
Flower weight FAQ
How many grams are in an eighth?
An eighth of an ounce of flower is 3.5 grams on most dispensary menus.
How many grams are in a quarter ounce?
A quarter ounce is 7 grams, or two eighths.
How many grams are in an ounce of weed?
An ounce is commonly treated as 28 grams for retail flower packaging.
Do shake and popcorn weigh the same as full buds?
Yes, if the package net weight is the same. The names describe form and size of the pieces, not a different unit of weight.
How much flower can a recreational customer buy in Colorado?
Adults 21 and older can buy up to one ounce of retail flower, or its equivalent, in a single transaction from a licensed store.
Who can buy retail flower in Colorado?
Adults 21 and older with a valid photo ID, and only from licensed retail stores.
