Like standard drinks for alcohol: 1 THC unit is 5 mg of THC. Works for flower, concentrates, edibles and oils.
Need concentrates, oils, exact numbers or past weeks? Switch to Advanced.
Results update as you type.
Nothing logged this week.
Your log stays in this browser only. Nothing is sent anywhere.
Flower and concentrates: mg THC = grams × 1000 × THC% ÷ 100
Edibles: mg THC = mg per piece × pieces
Oils and tinctures: mg THC = mg per ml × ml
Units: units = mg THC ÷ 5. For flower that is the same as 2 × grams × THC%.
This counts the THC in the product, not how much your body absorbs. Smoking, vaping and eating deliver different shares of it, and edibles take longer to act.
Adults should not exceed 8 THC units per week to reduce the risk of cannabis use disorder.
Source: Freeman, T.P. et al. (2025) 'Estimating thresholds for risk of cannabis use disorder using standard delta-9-tetrahydrocannabinol (THC) units', Addiction. doi.org/10.1111/add.70263
This tool is for education and harm reduction, not medical advice. The lowest-risk choice is not to use cannabis. If you are worried about your use, a GP or a local drug service can help.