How to calculate THC per serving in home-made edibles?

Multiply the weight of cannabis (in g) by its THC content, then by the decarboxylation efficiency and infusion yield. Then divide by the number of servings. Example: 5 g at 18 % THC decarboxylated in the oven (75 %) and infused in butter (93 %) yields around 628 mg active THC. For 12 cookies, that's 52 mg per cookie - a very high dose.

What dose of THC per serving is reasonable for a beginner?

Between 1 and 5 mg THC per serving. The reference dose in legalized US states is 10 mg - considered standard for an occasional user. For beginners, starting at 2.5 mg is prudent. Always wait at least 2 hours before evaluating the effect and repeating.

Do you have to decarboxylate before cannabuttering?

Yes, raw cannabis contains non-psychoactive THCA. Without prior decarboxylation, only 10 to 20 % of THCA converts to THC when infused in a hot fatty substance. Correct decarboxylation in the oven (110-115°C, 40 min) achieves a conversion rate of around 75 %.

Which oil to choose for infusing cannabis?

Coconut oil and butter offer excellent extraction performance (93 %) thanks to their high saturated fatty acid content. MCT oil (90 %) is ideal for capsules or salad dressings - it remains liquid and absorbs quickly. Olive oil (95 %) is suitable for savoury preparations. Alcohol (98 %) is reserved for tinctures.

Why can portions of the same batch have different doses?

Even in a well-homogenized cannabutter, THC is never perfectly distributed. Cannabinoids tend to concentrate in certain areas of the preparation. Calculations in this type of tool are averages - actual content per serving may vary by ± 20 % depending on recipe and technique.

Free tool

Edibles dosage calculator: THC per serving

Q: Why are the effects of edibles stronger than those of a joint?

When ingested, THC is metabolized by the liver into 11-hydroxy-THC, a more potent and longer-lasting metabolite than inhaled THC. This is why the effects of edibles are often more intense (even at equivalent doses) and last 4 to 8 hours, compared with 1 to 3 hours for inhalation.

Accurately estimate the amount of THC per serving in your homemade preparations: cannabutter, infused oil, cakes or tinctures. The tool incorporates real losses due to decarboxylation and infusion.

Updated : June 2026 Free & no registration required Sources cited

Calculator

Cannabis weight (g)

Total weight used for infusion

THC content (%)

Indicated on packaging or COA

Decarboxylation

Infusion base

Base quantity (g or ml)

Total quantity brewed

Base used in recipe (g or ml)

May be less than total quantity

Number of servings

ex : 12 cookies, 20 brownies

Total active THC

—

THC in the recipe

—

THC per serving

—

THC / tablespoon

—

mg / 15 ml

Dose level per portion

Calculations based on: decarboxylation efficiency (Perrotin-Brunel et al., 2011) and lipid absorption (Grotenhermen, 2003). Estimates may vary according to cannabis quality and infusion technique.

How to use this calculator

The main difficulty with edibles home is the inaccuracy of dosage. This calculator takes into account the two main losses that reduce the amount of THC actually present in your preparation: the effectiveness of the decarboxylation and fat infusion yield.

Inform cannabis Weight in grams and THC content indicated on packaging or certificate of analysis (COA).

Choose your decarboxylation method The classic oven activates about 75 % of the THCA. The hermetically sealed jar in water bath rises to 88 %. An already active concentrate (distillate, RSO) is 100 %.

Indicate your infusion base Butter, coconut oil, MCT oil or alcohol. Each fat has a slightly different extraction yield.

Distinguish between quantity brewed and quantity used If you infuse 200 g of butter but only use 150 g in your recipe, enter the two values separately.

Enter number of servings Total number of portions your recipe produces: cookies, brownies, capsules...

What formula does this tool use?

The calculation takes place in three successive stages:

THC raw = weight cannabis (g) × THC content (%) × 10 = mg potential THC
Active THC = raw THC × decarboxylation efficiency × infusion yield
THC per serving = Active THC × (quantity used ÷ total quantity) ÷ number of servings

Example: 5 g at 18 % THC = 900 mg crude. After decarboxylation in the oven (75 %) and infusion in butter (93 %): 900 × 0.75 × 0.93 = THC. 628 mg active. Divided into 12 portions : 52 mg per serving - a very high dose.

THC dosage guide per serving

THC per serving	Level	Recommended profile
1 - 5 mg	Light	Beginners, microdosing, high THC sensitivity.
5 - 10 mg	Standard	Occasional users. Reference dose in the United States (legalization).
10 - 20 mg	Moderate	Regular users. Wait 1 h 30 before repeating.
20 - 50 mg	High	Experienced users. Effects lasting 4 to 8 hours.
50 mg + + 50 mg + 50 mg + 50 mg + 50 mg + 50 mg + 50 mg + 50 mg	Very high	Risk of overdose. Reduce portions or amount of cannabis.

Why are edibles difficult to dose?

Time to act

Unlike inhalation (effects in 5 to 15 minutes), edibles pass through the digestive system. The effect appears between 30 minutes and 2 hours after consumption, sometimes more depending on the meal taken beforehand. The main cause of overdose is taking another dose before the first has taken effect.

Hepatic conversion

Ingested THC is metabolized by the liver into 11-hydroxy-THC, a more potent and longer-lasting metabolite than inhaled THC. This is why the effects of edibles are often described as more intense and longer-lasting (4 to 8 hours) than those of inhalation.

The uneven distribution of THC

Even in a cannabutter well homogenized, the THC is not perfectly distributed. Two cookies from the same batch may contain slightly different doses. The calculations in this tool are average estimates, not guaranteed values.

Cannabutter, coconut oil or tincture: which to choose?

The three bases allow THC to be infused effectively, but with different uses:

Butter Ideal for classic pastries (cookies, brownies, cakes). Rich flavor. Keep for 1 to 2 weeks in a cool place.
Coconut oil High saturated fatty acid content, excellent extraction yield. Vegan. Replaces butter in most recipes.
MCT oil Fast absorption, neutral taste, ideal for capsules or vinaigrettes. Remains liquid at room temperature.
Alcohol (tincture) Precise dosage in drops, rapid sublingual effect (15 to 30 min), long shelf life. Strong taste.

Scientific sources

Perrotin-Brunel, H. et al. (2011). Decarboxylation of Δ9-tetrahydrocannabinol: kinetics and molecular modelling. Journal of Molecular Structure, 987, 67-73.
Grotenhermen, F. (2003). Pharmacokinetics and Pharmacodynamics of Cannabinoids. Clinical Pharmacokinetics, 42(4), 327-360.
Huestis, M.A. (2007). Human Cannabinoid Pharmacokinetics. Chemistry & Biodiversity, 4(8), 1770-1804.
Barrus, D.G. et al. (2016). Tasty THC: Promises and Challenges of Cannabis Edibles. Methods Report (RTI Press).

Warning: The results of this calculator are estimates based on average decarboxylation and infusion values published in the scientific literature. Actual THC content may vary significantly depending on technique, equipment and quality of cannabis used. This tool does not constitute medical advice. The production and consumption of cannabis containing THC is illegal in France.