A Certificate of Analysis (COA) is the single most useful document a hemp buyer can learn to read. Whether you are looking at concentrates, vapes, or pre-rolls, knowing how to read a COA helps you verify what is actually in a product before you buy it. This guide walks through what a Certificate of Analysis is, why third-party testing matters, and how to interpret each section line by line.
What Is a Certificate of Analysis (COA)?
A Certificate of Analysis is a lab report that documents the results of testing performed on a specific batch of a hemp product. It is issued by a testing laboratory and typically covers cannabinoid potency along with screens for common contaminants. Reputable brands make the COA available for every batch they sell, so you can match the document to the exact product in your hand.
At Doc’s Hemp, products are made to order and every batch is third-party lab-tested, with a COA published on our Doc’s Hemp lab results page.
Why Third-Party Testing Matters
Not all lab results carry the same weight. A third-party (independent) lab has no financial stake in the outcome, which makes its results more credible than testing a company runs on itself. Independent testing is how a buyer can confirm that a product’s label matches what is inside, and how a brand demonstrates that it is Farm Bill compliant — meaning the product contains under 0.3% delta-9 THC on a dry-weight basis.
Just as important: if a product has no COA at all, you have no way to verify its contents. Untested products are the ones to avoid.
How to Read a COA, Section by Section
Most COAs follow a similar structure. Here is how to work through one.
Cannabinoid Potency
This section lists the cannabinoids detected and their concentration, usually as a percentage by weight and in milligrams per gram. For hemp products, two numbers matter most:
- THCA % — the amount of tetrahydrocannabinolic acid present.
- Delta-9 THC % — this must be under 0.3% for the product to meet the federal Farm Bill compliance threshold.
Compare the delta-9 THC figure against that 0.3% line. If it is at or below the threshold, the product is compliant on that measure.
Pesticides
This panel screens for agricultural chemicals. You want to see results reported as “pass,” “not detected,” or below the listed action limit for each analyte.
Heavy Metals
Because hemp can absorb metals from soil, COAs commonly test for lead, arsenic, cadmium, and mercury. Again, look for a “pass” or results under the stated limits.
Residual Solvents
Relevant to concentrates and extracts, this section checks for solvents that may remain after processing. A clean result shows these are absent or within accepted limits.
Microbials
This screens for microbiological contaminants such as certain molds and bacteria. A passing result indicates the batch fell within the lab’s thresholds.
Batch, Date, and Lab Accreditation
Finally, confirm the paperwork itself. A trustworthy COA shows a batch or lot number that matches the product, a test date, the sample name, and the name of the accredited laboratory that performed the analysis. If the batch number does not match the product, the COA does not describe what you are buying.
What to Look For on a COA
- An independent, third-party accredited laboratory named on the report.
- A batch or lot number that matches the product you are buying.
- A recent test date tied to that specific batch.
- Delta-9 THC listed under the 0.3% compliance threshold.
- Potency figures for cannabinoids such as THCA.
- “Pass” or within-limit results for pesticides, heavy metals, residual solvents, and microbials.
Buy Lab-Tested, Not Guesswork
Once you can read a COA, the standard becomes simple: if a product does not come with a matching, third-party Certificate of Analysis, treat it as unverified. Doc’s Hemp publishes a COA for every batch, ships to 41 states, and keeps documentation available for our lab-tested THCA concentrates and other products. Products are intended for adults 21 and older.
Want to see what a real COA looks like? Browse the Doc’s Hemp lab results and review the documentation for yourself before you buy.