Not very, according to the research, and that even includes some of our own labels. In a 2017 JAMA study of 84 CBD products bought online, only 31% tested within 10% of the amount on the label. About 26% had less CBD than labeled and 43% had more.
I would rather show you our numbers than tell you they are fine. The four batches below tested between 4% and 27% above their label claims, but always above. By the same 10% yardstick, three of the four fall outside the range, all on the high side. This guide covers what that means, why it happens, and how to read a lab report yourself.
Lab results differ from CBD labels for four reasons: a deliberate overage so the product still meets its label near the end of its shelf life, normal batch to batch variation, measurement differences between labs, and slow degradation over time. A result above the label is not the same as a result below it, but both are gaps between the bottle and the label, and you should be able to see them.
1. Our Lab Results vs. Label Claims
These are the lab-reported CBD amounts for four of our batches, compared with the amount printed on each label. The original reports are linked in Section 6 and hosted on mycbdtest.com, a third-party results site.
*Difference is the lab result minus the label claim, divided by the label claim. Amounts are CBD per container as reported on each batch's lab report.
Our goal is to always make sure that you get what you pay for. That is why all of our products test above our CBD label claim.
Some batches test higher than the label, and the Mint batch is the biggest example in this table. The formula does not change from batch to batch. What is checked every time is that the hemp extract tests ND for THC (LOD 0.0002%) and that the CBD is at or above what the formula requires. A batch that tests under the formula requirement does not ship. Extra CBD from the extract does not bring any THC with it, so a higher result is not a THC issue. It is still a gap from the label, which is why I show it here instead of hiding it.
I have perrsonally rejected a past batch. The problem was a clerical error on the record: the test date listed for the hemp extract used in that batch came after the production date, which cannot be right. A record I cannot trust is a record I will not ship on, so the batch was replaced.
2. What the Research Says About CBD Label Accuracy
Our numbers are not unusual for being imperfect. The published evidence points to three things: CBD labels are often off, different labs can report different results for the same sample, and CBD can degrade.
Two cautions. The JAMA study tested products bought in 2016 and the market has changed, so treat it as a snapshot and not today's rate. The Washington and California findings are about cannabis flower and oil potency, not CBD tinctures, and the degradation study used an e-liquid, not an oral product. They are still useful because they show the same problem: cannabinoids are hard to measure, and two competent labs can disagree.
3. Why Lab Results Differ From the Label
A deliberate overage
Many manufacturers formulate above the label claim so the product still meets the label near the end of its shelf life. It is a common approach for ingredients that can lose potency over time, such as some vitamins. The trade off is that a fresh bottle tests above its label, which is what you see in the table above.
Batch to batch variation
Crop variation, extract potency, mixing, and filling all vary a little from one production run to the next. That is why the same type of product can land at +4% in one batch and +27% in another.
Measurement differences between labs
A lab result is one measurement from one lab on one sample. As the studies above show, labs can report meaningfully different numbers for the same material. I treat a single result as a good estimate, not an exact figure, which is also why we publish the reports and not just a summary.
Slow degradation over time
CBD can break down, especially with light, heat, and oxygen. The 2022 study above found CBD degrading in an e-liquid at room temperature, and found very little change when samples were kept from light at 4 °C. That study was not an oral tincture, so it cannot tell us how much a sealed bottle loses. It does support the practical advice: keep CBD away from light and heat. For how we think about best-by dates, see our complete CBD shelf-life guide.
4. Is More CBD Than the Label a Good Thing?
I used to describe an overage as getting more for your money. I do not think that is the right way to say it. What you want from a label is that the bottle matches it, and your daily routine is set by how much you take, not by how far a batch lands above its label.
Here is what the gap means in practice. A 1 mL serving of a tincture labeled 30 mg would hold about 38 mg if the batch tests 27% high, and about 34 mg at +12%. That is a small difference for most adults, but it is real, so I wanted you to be aware of it.
I always recommend to check the lab rerport for the specific batch you have. Then you can use the exact number to determine your daily serving size. And, as always, talk to your doctor if you have any concerns or if you take prescription medication.
The one thing an overage does not change is THC. Each report linked in Section 6 lists THC and its related forms as not detected, at a detection limit of 0.0002%, so a higher CBD result does not bring THC with it.
5. How to Read a CBD Lab Report (COA)
A certificate of analysis, or COA, is the lab's report on one batch. This is how I read one. For a wider checklist, see our guide on what to look for when buying CBD oil.
If you want to compare products on cost, convert the label claim or the lab result to price per mg with our price per mg calculator.
6. Verify Your Own Batch
Your batch number is printed on your bottle or jar. These are the reports for the batches in the table, and our lab results page has more. For how we approach testing in general, see our CBD testing and trust guide.
- View CBD Mint Tincture Batch 260325A Results
- View CBD Mint Tincture Batch 251203A Results
- View CBD Orange Tincture Batch 241126A Results
- View CBD Sports Cream Batch 26089-06 Results
- View CBD Sports Cream Batch 25191-09 Results
- View CBD Gummies Batch 250222 Results
7. CBD Lab Results and Label Accuracy FAQ
Why is my CBD lab result higher than the label claim?
Usually for one or more of four reasons: the manufacturer formulates above the label on purpose so the product still meets the label near the end of its shelf life, the batch varied during production, the lab's measurement carries some uncertainty, or the product has degraded slightly. Our four batches above tested above their labels.
Is it normal for CBD lab results to differ from the label?
Yes. In a 2017 JAMA study of 84 online CBD products, only 31% were within 10% of the label. Labs also disagree with each other. A trade journal round robin sent the same homogenized cannabis oil to 10 labs and got potency results from 64% to 83%.
Is more CBD than the label a problem?
Not for THC, since our reports show none detected, but it is still a gap between the label and the bottle. A tincture labeled 30 mg per mL that tests 27% high delivers about 38 mg in a 1 mL serving, so always check the lab report for the bottle in your hand and adjust yourr daily serving size accorrdingly.
How do I convert a lab report result to total mg?
If the report gives mg per mL, multiply by the volume of the bottle. A 30 mL bottle at 38.2 mg per mL holds about 1,145 mg. If the report gives mg per gram or a percent, you need the weight of the contents to get the total.
What does ND mean on a CBD lab report?
ND means not detected, which means the amount was below the lab's limit of detection. Check the limit that is listed. On our reports the limit of detection for the THC forms is 0.0002%.
Where can I see the lab report for my batch?
Use the batch number printed on your bottle or jar. The reports for the batches in this guide are linked in Section 6, and more are on our lab results page.
