Pick up three CBD topicals and you will usually find three different ways of stating strength. One jar says "1,000 mg." Another says "500 mg CBD per oz." A third says "3,000 mg hemp extract" in large type and something smaller on the back. All three numbers are real, but they measure different things, and the biggest number on the shelf is often not the most concentrated product.
This guide explains the two figures you will see most, milligrams per jar and milligrams per ounce, how to convert between them, and the handful of label tricks that make products look stronger than they are. It is written for shoppers and for practitioners choosing a product for their practice. It is about reading labels accurately, not about what any CBD product will do for you.
Two numbers, two questions
Milligrams per jar (total mg) answers "how much CBD is in this whole container?" It is the number most brands print biggest, because it is the biggest number they have.
Milligrams per ounce (mg/oz) answers "how much CBD is in each ounce of product?" That is a concentration. It tells you how much CBD is in the amount you actually scoop out and put on your skin.
For a topical, concentration is usually the more useful figure. You do not apply a whole jar at once. You apply a fingertip or two. If two products are used in the same amount, the one with more mg per ounce puts more CBD on the skin with each application, whatever the jar size.
Total mg is still useful, just for a different job: working out cost per milligram and how long a container will last. You need both numbers, and you need to know which one you are reading.
Why a bigger total can mean a weaker product
Here is a made-up comparison with three hypothetical products (not real brands):
- Product A: 1,000 mg CBD in a 1 oz jar.
- Product B: 3,000 mg CBD in a 4 oz jar.
- Product C: 2,500 mg CBD in an 8 fl oz pump bottle of lotion.
On the shelf, Product B looks three times stronger than Product A, and Product C looks close behind. Divide total mg by ounces and the order flips:
- Product A: 1,000 ÷ 1 = 1,000 mg per oz
- Product B: 3,000 ÷ 4 = 750 mg per oz
- Product C: 2,500 ÷ 8 = about 313 mg per oz
The smallest jar is the most concentrated, and the product with the second-biggest headline number is the least concentrated by a wide margin. A fingertip of Product C carries roughly a third of the CBD of a fingertip of Product A. Nothing on the front of those three labels is false. It just answers a question you may not have been asking.
How to convert, step by step
From total mg to mg per oz
Divide the total CBD by the container size in ounces. If the container is listed in millilitres, convert first: 1 US fluid ounce is about 29.6 ml, so divide the millilitres by 29.6 to get fluid ounces.
Example: a 50 ml jar with 1,500 mg CBD. 50 ÷ 29.6 ≈ 1.69 fl oz. 1,500 ÷ 1.69 ≈ 888 mg per fl oz.
From mg per oz to total mg
Multiply the per-ounce figure by the container size in ounces. A label that says 800 mg per oz on a 2 oz tin implies about 1,600 mg in the tin.
From a lab report (mg/g) to mg per oz
Lab certificates usually report cannabinoids as milligrams per gram (mg/g). One ounce by weight is about 28.35 grams, so multiply mg/g by 28.35 to get mg per weight ounce. A report showing 40 mg/g works out to roughly 1,134 mg per weight ounce. This is how you check a label against its certificate of analysis (COA), which we come back to below.
The label details that trip people up
1. Fluid ounces vs weight ounces
"Oz" can mean volume (fluid ounces) or weight (ounces by mass). For water they are close; for balms, butters and oils they are not identical, because these products are not the same density as water. The difference is usually modest, but if you are comparing two products closely, check whether both labels use the same kind of ounce. Container sizes are often printed in both fl oz and ml, which helps.
2. "Hemp extract" or "hemp oil" mg instead of CBD mg
Some labels state the milligrams of hemp extract rather than the milligrams of CBD. Hemp extract contains CBD plus other plant compounds, carrier oil and so on, so the extract figure is larger than the CBD figure. A product that says "3,000 mg hemp extract" may contain far less than 3,000 mg of CBD. Look for the words "CBD" or "cannabidiol" next to the number.
3. Hemp seed oil is not CBD
Hemp seed oil is pressed from seeds and is a perfectly good skin oil, but it contains essentially no CBD. A product listing hemp seed oil (sometimes written as Cannabis sativa seed oil) with no separate CBD figure is not a CBD product in the sense this guide is about.
4. "Total cannabinoids" vs "CBD"
Broad spectrum and full spectrum products contain several cannabinoids. Some labels report the total of all of them. That is a legitimate figure, but it is not the same as CBD alone, so compare like with like.
5. Water counts toward the ounces
Creams and lotions are emulsions, which means water is a major ingredient and part of every ounce you buy. Waterless balms are made from oils, butters and waxes, so the space in the jar is taken up by those instead. Neither approach is wrong, but it is one reason lotions often show a lower mg per ounce than balms at a similar price. Our comparison of CBD balm vs cream vs lotion covers the texture and use differences in more detail.
6. No batch, no lab report
A potency number is only as good as the testing behind it. If a product does not link to a third-party COA, or the COA does not match the batch you are holding, you have no way to check the label figure at all.
Checking a label against its COA
A COA from an independent lab is the closest thing a shopper has to proof of what is in the jar. To use one for potency:
- Match the batch. The batch or lot number on the COA should match the one printed on your container, or at least the brand should tell you which batch you are getting.
- Find the CBD line. Look for "CBD" or "Total CBD" in the cannabinoid results, usually given in mg/g, and sometimes also per unit.
- Convert and compare. Use the mg/g × 28.35 conversion above and set the result next to the label figure.
- Expect some variance. Natural products and lab measurements both vary a little. A small gap between label and lab result is normal; a large one, or a COA that does not mention CBD at all, is a reason to ask the brand questions.
- Check the THC result too. If THC matters to you, the same report shows it. Note the lab's limit of quantitation (LOQ), the smallest amount the method can measure.
If you are buying for a clinic or spa, our guide to what to ask a wholesale CBD cream supplier has a fuller paperwork checklist.
Comparing price fairly: cost per milligram
Once you know total CBD, cost per milligram is simple: divide the price by the total mg of CBD. Using the hypothetical products above, if Product A costs $60 and Product B costs $90, then:
- Product A: $60 ÷ 1,000 mg = 6 cents per mg
- Product B: $90 ÷ 3,000 mg = 3 cents per mg
Product B is cheaper per milligram, but less concentrated per ounce. Which matters more depends on how you use it. Someone covering large areas of skin, or a practitioner using a product across many sessions, may care about total CBD and cost per mg. Someone applying a small amount to one spot may care more about concentration. The point is to choose on purpose rather than by the biggest number on the front.
How we state strength on Melrose Relieve
We print the concentration on the front of the jar: 2,000 mg CBD per oz. The jar size, 100 ml (3.38 fl oz), is printed beside it, so you can do your own math with the method above. Melrose Relieve is a waterless balm, broad spectrum, labeled 0% THC, made in small batches, and developed by massage therapists. The third-party lab reports for the current batch are public on our lab results page, so you can check the figures against the certificate rather than taking our word for them.
We are a CBD brand, so we are not neutral. Use the same checklist on our jar that you would use on anyone else's. If you want a broader primer on topicals first, start with what CBD cream is and how topicals work. Practitioners can find pricing on our professionals page.
Frequently asked questions
Is mg per jar or mg per oz the better measure of CBD strength?
For a topical, mg per ounce is usually the better measure of strength, because it describes how much CBD is in the amount you actually apply. Total mg per jar is useful for working out cost per milligram and how long a container will last.
How do I convert mg per jar to mg per oz?
Divide the total milligrams of CBD by the container size in ounces. If the size is in millilitres, divide by about 29.6 first to get US fluid ounces. For example, 1,500 mg in a 50 ml jar is about 888 mg per fluid ounce.
Why can a cream with more total mg be less concentrated than a small balm?
Total mg says nothing about concentration. A large bottle of lotion can hold more CBD overall but much less per ounce, partly because water makes up a large share of most creams and lotions. Compare products on mg per ounce to see which carries more CBD per application.
Is hemp extract mg the same as CBD mg?
No. Hemp extract contains CBD plus other plant compounds and carrier material, so an extract figure is larger than the CBD figure. Look for a number labeled CBD or cannabidiol, and check it against a third-party certificate of analysis.
How do I check a CBD label against the lab report?
Match the batch number, find the CBD result on the certificate of analysis (usually in mg per gram), multiply by 28.35 to get mg per weight ounce, and compare that with the label. A small gap is normal; a large gap or a missing CBD result is a reason to ask the brand.
How strong is Melrose Relieve?
The label states 2,000 mg CBD per oz in a 100 ml (3.38 fl oz) jar. It is broad spectrum, labeled 0% THC, and the third-party lab reports are on the Melrose Essentials lab results page.
These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. Consult your physician before use, particularly if you are pregnant, nursing, or taking medication.
