Converting Potency from mg/g to %

Converting Potency from mg/g to %


  • All products will display THC/CBD in mg/g or total milligrams.
  • Existing categories will have a year grace period to change labels.

Since went live in October 2018, many customers have become familiar with flower potencies being listed as percentage values.

With the revised regulations, all new categories must display the potency/concentration in milligrams per gram (mg/g) or total quantity in milligrams (mg), depending on the class of cannabis and immediate container. Another label change to note is that cannabis oil sprays (and any cannabis extract in a container with an integrated dispensing mechanism) will display the total THC & CBD per activation in milligrams. Oils will change from mg/ml to mg/g – a basic conversion is nearly one to one (the agreed density of grams to volume is 0.93 g/ml).

Existing categories (dried flower, oils and capsules) have been given a 12-month grace period to allow suppliers time to transition, so you should expect some variation and exceptions during this time.

Flower and pre-roll products will be the biggest change, but the conversion method from mg/g to % is easy once known:

Simply move the decimal point one spot to the left to figure out the percentage of THC or CBD.

For example, if the flower is listed as 200mg/g of THC then it will contain 20% THC. Here’s how the formula works:  There are 1000mg in a gram, so first we divide the mg/g and then we multiply it by 100 to get a percentage:

200mg/1000mg (1g) = 0.20

0.20 x 100 = 20%

For reference, here are some common potencies in both mg/g and their % equivalent:

 Mg/g %
50mg/g 5%
100mg/g 10%
150mg/g 15%
200mg/g 20%
300mg/g 30%
500mg/g 50%
1000mg/g 100%


All products will feature their net weight in grams, with the exception of beverages, where the volume must be represented in milligrams.

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