When shopping for a hemp product, you may see a link or QR code labeled “Lab Results” or “Certificate of Analysis.” This document—usually called a COA—provides information about a product or production batch based on laboratory testing.
A COA may look complicated at first. It can include unfamiliar cannabinoid names, percentages, reporting limits, testing dates, and several pages of laboratory data. Fortunately, you do not need to be a scientist to understand the most important parts.
Here is a straightforward guide to reading a hemp COA and checking whether it matches the product you are considering. View Our Lab Results
What Is a Certificate of Analysis?
A Certificate of Analysis is a report produced by a testing laboratory after analyzing a sample.
Depending on the type of product and testing requested, a COA may report:
- Cannabinoid potency
- Delta-9 THC and THCa concentrations
- Pesticides
- Heavy metals
- Microbial contaminants
- Mycotoxins
- Residual solvents
- Moisture or water activity
Not every COA includes every category. Some reports test only cannabinoid potency, while others include a broader safety-testing panel.
The FDA has repeatedly flagged concerns about hemp and cannabis-derived products that don’t contain the cannabinoid levels stated on their labels or that may carry contaminants such as pesticides and heavy metals. A readable, product-specific COA gives customers a way to examine available testing information before purchasing.
Step 1: Check the Laboratory
Start by identifying the laboratory that issued the report.
The laboratory’s name, address, contact information, certification details, and report number will usually appear near the top of the first page.
A trustworthy report should clearly identify the laboratory. It should not look like a spreadsheet created by the seller, a cropped screenshot, or a document with the laboratory information removed.
In Colorado, hemp testing laboratories must be certified by the Colorado Department of Public Health and Environment (CDPHE) to perform specific categories of testing, and the state maintains a public list of certified hemp testing laboratories and the testing categories each one is approved to perform.
Laboratory certification does not guarantee that every product is perfect. It does, however, help establish that the report came from an identifiable testing facility operating under defined standards.
Step 2: Match the COA to the Product
A COA is useful only when it can be connected to the product being sold.
Look for identifying information such as:
- Product or strain name
- Batch number
- Lot number
- Sample identification number
- Production date
- Collection date
- Testing date
Compare this information with the product label or the product description on the seller’s website.
The batch or lot number is especially important. Two packages with the same product name may come from different harvests or production runs, and their results may not be identical.
A generic COA that does not identify a product or batch provides less useful information than a report clearly tied to the item being offered.
Step 3: Review the Testing Dates
Next, check when the sample was received and when the testing was completed.
A COA commonly includes several dates:
- Date collected
- Date received by the laboratory
- Date tested
- Date the report was issued
The report does not necessarily need to have been issued recently. Properly stored flower or finished products may remain associated with the same valid production batch for some time.
The important question is whether the COA corresponds to the batch currently being sold. A recent product should not be paired with an unrelated report from an older batch simply because the product names are similar.
Step 4: Find the Cannabinoid Profile
The cannabinoid section is usually the part customers notice first.
It may list compounds such as:
- THCa
- Delta-9 THC
- CBDa
- CBD
- CBG
- CBN
- CBC
The exact list will depend on the product and the laboratory’s testing panel.
Results may be displayed as a percentage, milligrams per gram, milligrams per unit, or a combination of measurements.
For flower, cannabinoid results are often shown as a percentage by weight. For example, a result of 20% THCa represents approximately 200 milligrams of THCa per gram of tested material.
These numbers describe the tested sample. They should not be treated as a guarantee that every piece of plant material will contain the exact same concentration. Hemp is an agricultural product, and some natural variation may occur within a batch.
Step 5: Understand THCa, Delta-9 THC, and Total THC
THCa and delta-9 THC are related, but they are not the same measurement.
THCa, or tetrahydrocannabinolic acid, is a cannabinoid found naturally in raw cannabis and hemp material. Heat can convert a portion of THCa into delta-9 THC through a process called decarboxylation.
Delta-9 THC is listed separately on most cannabinoid reports.
You may also see a line labeled Total THC. Under USDA regulations governing hemp testing, Total THC is calculated using a post-decarboxylation method (or an equivalent conversion factor) so the reported number reflects the potential delta-9 THC that could result from the conversion of THCa, not just the delta-9 THC already present in the sample.
Do not assume that the largest number on a COA is the only number that matters. Read the headings carefully and distinguish among THCa, delta-9 THC, and calculated Total THC.
Step 6: Understand Common Laboratory Abbreviations
COAs often use abbreviations to describe very small results or values below the laboratory’s reporting threshold.
Common examples include:
ND — Not Detected
The laboratory did not detect the substance above its established detection limit. ND does not always mean that absolutely none of the substance exists. It means the test did not detect it at or above the method’s stated limit.
LOQ — Limit of Quantitation
This is the lowest amount the laboratory can reliably measure and report as a numerical result.
LOD — Limit of Detection
This is the lowest concentration the laboratory’s method can detect, although it may be too small to measure precisely.
Pass
The tested sample met the limit used by the laboratory for that particular analysis.
Always check what was actually tested. A “Pass” result for pesticides does not automatically mean the same sample was also tested for heavy metals, microbes, or residual solvents.
Step 7: Review Contaminant Testing
A more comprehensive COA may contain several safety-testing sections.
Pesticides
This section checks for specific pesticide compounds included in the laboratory’s panel. Results may be reported individually as Pass, ND, or as measured concentrations.
Heavy Metals
Commonly tested metals may include lead, arsenic, cadmium, and mercury.
Microbial Contaminants
Microbial testing may screen for organisms such as certain bacteria, yeast, or mold.
Mycotoxins
Mycotoxins are harmful compounds that may be produced by certain molds.
Residual Solvents
This testing is most relevant to products manufactured using extraction or processing solvents. It may be less applicable to unprocessed flower.
Colorado-certified laboratories are approved by category, which may include cannabinoids, pesticides, metals, microbes, mycotoxins, moisture, and residual solvents. A laboratory’s certification scope helps show which analyses it is authorized to perform.
Step 8: Look for Signs of an Incomplete or Questionable COA
A COA deserves a closer look when:
- The laboratory is not identified.
- The report has been cropped or altered.
- The product and batch cannot be matched.
- The testing dates are missing.
- The report covers only potency but is described as “full-panel tested.”
- Pages containing contaminant results are missing.
- The QR code leads to a different product.
- The product label makes claims that do not match the reported results.
- The seller will not provide the complete report.
A transparent seller should make it reasonably easy for customers to locate the available report and understand which product and batch it covers.
What a COA Cannot Tell You
A COA is an important transparency tool, but it has limits.
It reports the laboratory’s findings for the sample it received. It does not prove that a product will produce a particular experience, and it does not establish that a hemp product can diagnose, treat, cure, or prevent a medical condition.
The FDA has repeatedly warned companies against marketing cannabis-derived products with unsupported medical or therapeutic claims. Other than specifically approved prescription drugs, cannabis-derived retail products should not be presented as approved medical treatments.
A COA should therefore be viewed as a source of product and testing information—not as medical advice.
Our Approach to Product Transparency
We believe customers should be able to review available laboratory information before making a purchase.
Our goal is to provide clearly identified lab reports connected to the applicable product or batch. We encourage customers to review the laboratory name, batch information, testing date, cannabinoid profile, and the specific testing panels included in each report.
Questions about a report should be addressed before purchasing the product.
For adults 21 and older. Keep all hemp products away from children and pets. Do not drive or operate machinery after consuming an intoxicating product. Laws governing hemp products vary by location, and customers are responsible for understanding the laws applicable to them.
Sources
- U.S. Food and Drug Administration, FDA Regulation of Cannabis and Cannabis-Derived Products, Including Cannabidiol (CBD) — fda.gov
- U.S. Food and Drug Administration, Warning Letters for Cannabis-Derived Products — fda.gov
- USDA Agricultural Marketing Service, Laboratory Testing Guidelines, U.S. Domestic Hemp Production Program — ams.usda.gov
- 7 CFR Part 990, Domestic Hemp Production Program — ecfr.gov
- Colorado Department of Public Health & Environment, Hemp Testing Laboratory (HTL) Certification Process — cdphe.colorado.gov
- Colorado Department of Public Health & Environment, Certified Hemp Laboratories — cdphe.colorado.gov