mg vs percentage THC is one of those label puzzles that can make you second-guess a perfectly normal purchase. You pick up a flower jar that reads 20% THC, then you see a gummy that says 10mg THC, and your brain wants those numbers to “line up.” They do not. They are talking about two different things, and once you know which question each one answers, shopping gets a lot less confusing.
We are going to walk you through what THC percentage actually means, what “mg per serving” is really telling you, and why the word “strong” depends on the format and your own routine. You will also get a quick, usable conversion for flower, plus a simple way to sanity-check potency using lab reports instead of hype.
mg vs percentage THC: two label styles that measure different things
Think of cannabis potency like cooking.
- THC percentage is like how concentrated an ingredient is in the recipe.
- Milligrams of THC is like the exact amount you are about to eat or drink.
That is why you usually see percent on inhalable products like flower or concentrates, and milligrams per serving on edibles, beverages, tinctures, and capsules. A percent label helps you compare products within the same category. A milligram label helps you repeat a dose on purpose.
What does THC percentage mean, really?
THC percentage is a weight-based concentration. If flower is labeled 20% THC, that means roughly 20% of the dry weight is THC. Since 1 gram equals 1,000 milligrams, you can estimate the total THC in that gram pretty easily.
Regulators teach it this way for a reason. Higher-concentration products can increase the chance of unpleasant effects for some people, especially if you are not used to THC. The Washington State Liquor and Cannabis Board’s THC concentration and potency guide does a solid job explaining why concentration matters and why labels are structured differently across product types.
Typical THC percentage ranges you will run into:
- Flower: often around 10% to 30% THC
- Concentrates: often much higher, commonly 60% to 90% THC
- Kief or hash: often in the middle, commonly 50% to 80% THC
mg vs percentage THC for edibles: why milligrams are easier to use
Milligrams are straightforward because they are an absolute amount. If a chew says 10mg THC, that piece contains 10 milligrams of THC. No math, no guesswork.
Two quick label habits we recommend:
- Check mg per serving so you know what one piece (or one sip) is designed to be.
- Check mg per package so you do not accidentally treat the whole bag like one serving.
If you like dosing that feels consistent from day to day, edibles and beverages are often the easiest place to start, as long as you respect the timing. If you want a simple example of a clearly portioned format, our THC CannaChews (10mg Delta-9 THC per chew) are built around repeatable serving sizes.
mg vs percentage THC conversion: a quick way to estimate mg per gram
If you are looking at flower and want a fast estimate of total THC in the material, use this:
THC% × 10 = estimated mg of THC per gram
- 22% THC flower is about 220mg THC per gram.
- 15% THC flower is about 150mg THC per gram.
One important reality check: that number is the THC in the product, not the THC your body necessarily absorbs. Smoking and vaping vary by temperature, technique, and the way your body processes inhaled cannabinoids. So treat the conversion as a comparison tool, not a promise.
Why you cannot compare 20% THC flower to a 20mg edible
This is where most label confusion lives: percent is concentration, while mg on an edible is a swallowed dose. Those routes of use behave differently.
- Inhaled THC tends to come on faster, and the experience often resolves sooner.
- Edible THC takes longer to show up and can hang around longer.
With edibles, THC is processed through the liver and converted into a metabolite called 11-hydroxy-THC. Many people report that it can feel more intense and longer-lasting than inhaled THC, even at a dose that looks “small” on the label. For a science-forward overview of THC metabolism, including 11-hydroxy-THC formation, you can review the NCBI Bookshelf pharmacology summary on cannabis.
| Label type | Common formats | What it tells you | What it does not tell you |
|---|---|---|---|
| THC % | Flower, vapes, concentrates | Concentration (estimated mg THC per gram) | Your exact dose in a session |
| mg THC | Edibles, beverages, tinctures, capsules | Exact amount per serving | Exactly how fast or intense it will feel for you |
Are THC percentages reliable? Use a COA, not a vibe
THC labels are useful, but they are not perfect. A peer-reviewed analysis in PLOS ONE on labeled vs tested cannabis potency found that measured THC levels were often lower than what labels reported. That does not mean every product is off, but it is a strong argument for checking third-party lab testing when you can.
We treat lab reports as a baseline trust signal. If you want to verify potency, cannabinoid profiles, and batch details before you buy or consume, use our Product Test Results hub to look up third-party Certificates of Analysis by product type and batch.
How to choose the right metric when you shop
Use the metric that matches the format, then choose based on how much control you want over dose and timing.
- Flower, pre-rolls, vapes, concentrates: use THC percentage to compare concentration within the same category.
- Edibles and beverages: use mg per serving to control your dose.
If you are newer to THC or getting back into it after a break, keep your plan simple. Start low, go slow, and give edibles and drinks enough time before you consider taking more. And, of course, only use THC if you are 21+, do not drive after consuming, and store products securely away from kids and pets.
FAQ: mg vs percentage THC labels
What does THC percentage mean in plain English?
It is how concentrated THC is by weight. As a rough estimate, 20% THC flower works out to about 200mg THC per gram of flower.
Is 20% THC “stronger” than 10mg THC?
Not as a direct comparison. 20% is a concentration in a smokable or vapable product. 10mg is a swallowed dose. Depending on how much you consume and how your body handles edibles, 10mg can feel surprisingly strong.
How is THC potency measured for edibles?
Usually in milligrams per serving and total milligrams per package, because you are meant to consume a measured portion.
How do I compare flower strains if I only have THC %?
Compare percent within flower, then pay attention to how much you actually use in a session and how it fits your tolerance. If you want a quick estimate of THC content, use THC% × 10 to approximate mg per gram. For other tips on product selection, see our guide to the entourage effect and cannabinoids.
Where can I verify potency for Carbon Cannabis products?
You can check batch-specific lab testing in our third-party COA Test Results hub. Matching the product name and batch number is the simplest way to confirm you are looking at the right report.
Conclusion
mg vs percentage THC gets easy once you stop trying to force the numbers to mean the same thing. Percent tells you concentration, which helps you compare flower to flower or concentrate to concentrate. Milligrams tell you dose, which is what you want for edibles and beverages. When in doubt, choose the format that fits your routine, start low and go slow, and rely on third-party COAs so you know what you are actually consuming. If you need personalized recommendations, visit our Contact page to connect with a Carbon team member.
