Understanding how much tetrahydrocannabinol (THC) ends up in each serving of a homemade edible is simpler than most people expect, but only if you account for the right variables. This guide walks you through the conversion formula, explains where potency gets lost along the way, and gives you a reference table to put your final number in context.
Why Edible Potency Calculations Are Often Wrong, and How to Fix Them
Most potency calculations go wrong before the math even starts, because of a labeling detail that dispensaries rarely explain. When a package reads “20% THC,” it almost always means 20% tetrahydrocannabinolic acid (THCA), not active THC. THCA is the raw, non-intoxicating precursor that converts to THC during decarboxylation.
That conversion happens at roughly 87.7% efficiency, meaning 1 gram of 20% THCA flower yields closer to 175 mg of available THC after heating, not the 200 mg a direct percentage calculation would suggest.
The second common error involves the infusion loss factor. The standard formula applies a 0.80 multiplier to account for losses during cooking, but that single number bundles together two separate processes: the decarboxylation conversion above and the extraction efficiency of whatever fat or solvent you are using.
Butter, coconut oil, and alcohol tinctures each bind cannabinoids at different rates, so a fixed 0.80 will overestimate potency for some methods and underestimate it for others. Veriheal’s edible dosage calculator allows for solvent-adjusted inputs precisely because that single multiplier is not accurate enough for every infusion type.
Knowing both of these issues before you run the formula means your calculated milligram figure reflects what will actually end up in your food, not what the label implies.
How to Convert Cannabis Flower Potency to Edible Dosage: Step-by-Step
Use this formula to calculate total THC in your infusion, then divide by servings:
- Total mg THC per serving = (THC% ÷ 100) × grams used × 1,000 × decarb efficiency × extraction efficiency ÷ number of servings
Step 1: Find your total mg THC in the infusion
Start with your flower’s THC percentage. If the label reads 20% THCA and you are working with raw flower, multiply by 0.877 to correct for the molar conversion loss before doing anything else. If you are using a distillate or concentrate where decarboxylation has already occurred, input the THC percentage directly.
Step 2: Account for infusion loss
Multiply your available THC figure by your extraction efficiency. A general estimate of 0.80 works as a starting point, but the section below covers how this varies by solvent type.
Step 3: Divide by number of servings
Divide the result by however many portions your recipe produces.
Example:
7g of 20% THCA flower: 20% × 1,000 mg/g = 200 mg THCA per gram, so 7g contains 1,400 mg theoretical THCA. Corrected for decarb: 7 × 200 × 0.877 = 1,227.8 mg available THC after decarb. After 0.80 infusion loss: 1,227.8 × 0.80 = 982 mg total. Across 20 servings: 982 ÷ 20 = 49 mg per serving.
For a quicker estimate using the uncorrected label percentage: 7 × 200 × 0.80 ÷ 20 = 56 mg per serving. The difference between those two numbers is why the THCA correction matters.
How Decarboxylation Loss Affects Your Conversion Math
Raw cannabis flower contains THCA, not active THC. Heat drives off a carbon dioxide molecule during cannabis decarboxylation, converting THCA into the THC your body actually processes. That reaction is capped by simple stoichiometry: THC’s molecular weight (314.47 g/mol) divided by THCA’s molecular weight (358.47 g/mol) works out to approximately 87.7%, since the reaction sheds a CO2 molecule (44.01 g/mol) in the process.
Real-world decarboxylation in a home oven typically falls short of this theoretical maximum due to uneven heat exposure and some cannabinoid degradation, but 87.7% remains the standard benchmark used in dosage math.
Here is how that changes the math for a typical home cook using 1g of 20% flower:
- Label claim: 1g × 20% × 1,000 = 200 mg THC (uncorrected)
- After decarb correction: 200 × 0.877 = 175.4 mg available THC
- After infusion loss (0.80): 175.4 × 0.80 = 140.3 mg in the finished infusion
If you are working with a distillate, a CO2 extract, or any product labeled as active THC rather than THCA, skip step 2. The conversion has already happened, and applying the 0.877 factor again would underestimate your potency. Understanding where decarb loss fits in the sequence is the fastest way to close the gap between what you calculate and what you actually consume.
How Infusion Efficiency Varies by Solvent
The solvent you choose to infuse cannabis coconut oil, butter, or alcohol into changes how much THC actually binds during the process. These are practical ranges drawn from common home infusion conditions. Temperature, duration, and fat saturation all shift outcomes within the ranges below, so treat them as starting estimates rather than guarantees.
The standard 0.80 multiplier in the formula is a reasonable middle estimate for butter or coconut oil under good home conditions. If you are infusing cannabis coconut oil for the first time, using the Veriheal dosage calculator with the solvent-specific input field will give you a more accurate output than applying a flat 0.80 to every batch. Using olive oil and expecting 80% extraction efficiency means your servings will be weaker than you planned.
Common Mistakes in Edible Dosage Conversion
Even a correct formula produces a wrong answer if the inputs are off. These are the four mistakes that consistently skew homemade edibles dosage calculations:
- Reading the label as THC when it says THCA. Most dispensary flower is labeled in THCA percentage, not active THC. Inputting 20% THCA as 20% THC inflates your starting figure by about 12.3% before any other losses are factored in. Check the label carefully and apply the 0.877 decarb correction if the cannabinoid is listed as THCA.
- Using a single extraction efficiency for every solvent. The formula’s 0.80 default assumes butter or coconut oil under decent home conditions. Using the same figure for olive oil or a quick stovetop tincture will overstate how much THC made it into your final product.
- Ignoring portion inconsistency. Dividing by the number of servings only works if each serving contains the same amount of infused fat. Uneven mixing in brownie batter or a gummy mold that fills unevenly means your calculated per-serving dose applies to the average piece, not every piece.
- Skipping the decarboxylation step entirely. Raw flower added directly to a recipe without prior decarboxylation will not fully activate its cannabinoids, because cooking temperatures in most baked goods do not reach the sustained heat needed for complete THCA-to-THC conversion. A dedicated decarb step before infusion is what makes the math reliable.
Using the Edible Dosage Calculator for Accuracy
Running the formula manually is useful for understanding the math, but Veriheal’s edible dosage calculator handles the THCA correction, solvent-specific efficiency, and per-serving division in one step. You input your flower’s THC or THCA percentage, the amount used, your solvent type, and the number of servings, and the tool returns a milligram figure that accounts for each loss variable separately rather than bundling them into a single coefficient.
This matters most when you are switching between solvent types or working with a product that has already been decarbed. The calculator’s input fields reflect the actual steps in the conversion sequence, so the output is as accurate as the information you put in. For consistent batches over time, using the same calculator inputs each time also gives you a reliable baseline to adjust from if a batch comes out stronger or weaker than expected.
What Your Calculated mg Per Serving Actually Means: A Dosage Tier Reference
A milligram number on its own means nothing without context. Once you have calculated your per-serving THC dose, use the info below to place it against standard experience tiers.
These tiers are reference points, not guarantees, because how edibles affect your body differs from inhalation in one important way: the liver converts THC into 11-hydroxy-THC, a more potent metabolite that produces a longer and often more intense effect than the same dose inhaled. Tolerance, body weight, and stomach contents all shift where on this scale you will actually land.
How food intake affects cannabis effects varies significantly depending on whether you have eaten recently. If you are a beginner to edibles, start at the low end regardless of your calculated number, and wait at least 90 minutes before considering a second dose. If you ever need guidance on what to do if edibles hit too hard, our resource covers practical steps for managing an unexpectedly strong experience.
Before starting your edible journey, speak with a licensed cannabis physician to ensure that you’re covered in all aspects from a medical perspective..
Note: The content on this page is for informational purposes only and is not intended to be professional medical advice. Do not attempt to self-diagnose or prescribe treatment based on the information provided. Always consult a physician before making any decision on the treatment of a medical condition.
Note: Veriheal does not support illegally consuming therapeutic substances such as cannabis but acknowledges that it transpires because of the current illicit status, which we strive to change by advocating for research, legal access, and responsible consumption. Always consult a physician before attempting alternative therapies.
Frequently Asked Questions
How do I calculate the potency of homemade edibles?
To calculate edible potency, multiply your flower’s THC percentage (as a decimal) by the grams used, then by 1,000 to convert to milligrams. Apply your decarboxylation efficiency (roughly 0.877 for raw flower) and your infusion efficiency (typically 0.50 to 0.90 depending on solvent), then divide by the number of servings. The result is your estimated mg THC per serving.
How many mg are in a gram of 20% THC flower?
A gram of flower labeled 20% THCA contains a theoretical 200 mg of THC before any processing. After decarboxylation at approximately 87.7% efficiency, around 175 mg of active THC is available for infusion. Infusion losses reduce that figure further depending on your solvent and method.
How much THC is lost when making cannabutter?
Butter typically extracts 50 to 70% of available THC under home conditions, meaning 30 to 50% of your decarbed THC does not make it into the finished cannabutter. The exact figure depends on temperature, infusion time, fat content, and how thoroughly the mixture is strained.
How do I know how strong my cannabutter is?
Calculate the total mg THC in your infusion using the formula above, then divide by the total volume of butter produced. This gives you a mg-per-tablespoon or mg-per-gram figure you can apply to any recipe calling for that butter.
How many mg of THC are in a serving of edibles?
Standard commercially produced edibles contain 5 to 10 mg of THC per serving in most regulated markets. Homemade edibles vary widely depending on flower potency, infusion method, and batch size, which is why calculating your specific milligram figure before portioning matters.
What’s the best way to portion homemade edibles?
For baked goods, mix your infused fat as thoroughly as possible before combining with other ingredients, then cut finished pieces to a consistent size. For gummies or chocolates, weigh each portion before setting. Consistent portioning is the only way to ensure each serving reflects your calculated dose.
Can I calculate cannabidiol (CBD) edibles the same way as THC edibles?
Yes. The same conversion formula applies to CBD flower and cannabidiol-dominant infusions. Replace the THC percentage with your flower’s CBD or cannabidiolic acid (CBDA) percentage and apply the same decarboxylation and extraction efficiency factors. CBD and THC behave similarly during infusion, so the math holds across both cannabinoids.
