To calculate THC per serving in homemade edibles, multiply the weight of your cannabis by its THC concentration, apply a decarboxylation factor and an extraction-efficiency estimate, then divide the total milligrams of THC by the number of equal servings. The result is an estimate rather than a lab-verified number, so treat it as a starting point and dose low.
cannabis tincture dosage calculator
The formula at a glance
Total THC (mg) = grams of cannabis × 1,000 × (THC% ÷ 100) × decarb factor × extraction efficiency
how many mg of thc should i take
THC per serving (mg) = Total THC ÷ number of servings
thc edible dosage calculator
Each input matters. An error in any one of them carries straight through to your final dose per piece.
Step 1: Find the THC percentage of your starting material
Start with the number on the label of your flower or concentrate. Legal-market products in the US list THC and THCA percentages, and those figures give you the best available estimate of potency.
- If the label lists total THC, use that number directly.
- If it lists THCA and THC separately, you will need the conversion step below.
- If you have no label, assume a moderate to high potency and keep servings small. Unlabeled flower can vary a great deal.
- One gram of cannabis at 20% THC contains about 200 mg of THC.
Step 2: Account for decarboxylation
Raw cannabis contains THCA, which is not psychoactive. Heat converts THCA into THC, and that conversion is not complete. The commonly used multiplier is 0.877, which comes from the difference in molecular weight between the two compounds.
Total THC = THC + (THCA × 0.877)
If your label already reports total THC, skip this step. If you decarb at home, keep the temperature moderate and the time consistent. Heat that is too high for too long degrades THC instead of creating more of it.
Step 3: Estimate extraction efficiency
Infusing butter, oil, or alcohol never pulls out every milligram. Some THC stays locked in the plant material, some clings to the pan, and some is lost to straining. Planning ranges of 60% to 90% are common, depending on your method, infusion time, temperature, and the fat content of your base.
Pick one number, write it down, and use the same number every batch. A conservative estimate of 70% to 80% keeps your doses on the safer side.
Step 4: Divide by your real serving count
Count the pieces you actually produce, not the number you intended to produce. If you cut a tray into 48 squares, your serving count is 48. If you use a mold with 24 cavities, it is 24.
For the most even dosing, weigh the finished batch, divide total THC by total batch weight, then multiply that per-gram figure by the weight of each piece.
Worked example
You infuse 3.5 grams of flower labeled at 20% THC.
- 3.5 g × 1,000 = 3,500 mg of plant material.
- 3,500 × 0.20 = 700 mg of potential THC.
- 700 × 0.80 extraction efficiency = 560 mg in your butter.
- 560 ÷ 56 servings = 10 mg per piece.
If 56 pieces is awkward for your pan, cut 28 pieces at about 20 mg each and split them in half before eating.
How to keep servings even
- Grind and decarb the cannabis evenly so no clumps carry extra potency.
- Stir the infusion well before combining it with your batter.
- Stir the batter again right before pouring, since cannabinoids can settle.
- Use a mold with identical cavities or weigh pieces on a kitchen scale.
- Let the batch cool and set completely before cutting.
- Keep a written log of grams used, potency, efficiency estimate, and serving count.
Why the final number is an estimate
Potency varies from bud to bud within the same jar. Decarboxylation efficiency depends on your oven and timing. Extraction losses depend on your method. Home test kits and laboratory testing can narrow the gap, but for most kitchens the calculation above is a planning tool. It tells you roughly what one piece contains so you can avoid a surprise.
Safety basics
- Label every container with the estimated mg per serving and the date.
- Store edibles away from children and pets, ideally in a locked space.
- If you are new to edibles, start at 2.5 mg to 5 mg and wait up to two hours before taking more.
- Do not drive after consuming, and avoid mixing with alcohol.
Accurate math plus a conservative starting dose is the difference between a predictable evening and an uncomfortable one.