An ounce (oz) is 28.35 g (avoirdupois), rounded to 28 g when cannabis is sold. Slang names include "zip" (from zip-lock bags), "O" and "onion".
In practice
Many personal possession limits are written in ounces or in grams close to an ounce, for example 30 g in some places and 1 oz in others. The exact limit, and whether it covers dried flower only or equivalents, depends on the jurisdiction; check local rules.
For yield, growers often talk in ounces per plant or per light. "Two zips off one plant" means about 56 g dry.
Units and formula
| Slang | Nominal weight | Metric |
|---|---|---|
| Gram | 1 g | 1 g |
| Eighth | 1/8 oz | 3.5 g (exact: 3.54 g) |
| Quarter | 1/4 oz | 7 g |
| Half | 1/2 oz | 14 g |
| Ounce (zip, O) | 1 oz | 28 g (exact: 28.35 g) |
| QP | 1/4 lb (4 oz) | 113 g |
| Pound (elbow, LB) | 1 lb (16 oz) | 454 g (exact: 453.6 g) |
Retail rounds an eighth to 3.5 g and an ounce to 28 g.
Don't confuse with
- Troy ounce: 31.1 g, used for precious metals, not cannabis.
- Fluid ounce: a volume, not a weight.
A gram (g) is the base metric unit for weighing cannabis flower and concentrates; 28 g make a retail ounce and 3.5 g an eighth.An eighth is one-eighth of an ounce of cannabis, sold as 3.5 grams; it is the standard retail unit for flower in North America.A QP is a quarter pound of cannabis: 4 ounces, about 113 grams.Elbow is slang for a pound of cannabis, 16 ounces or about 454 grams, from the spoken abbreviation "L-B".A possession limit is the maximum amount of cannabis a person may legally carry or keep, usually set by weight of dried flower or an equivalent.
