Every quality cannabis and hemp product should come with a Certificate of Analysis (COA) from an independent third-party laboratory. This document tells you exactly what is in the product you are buying, how potent it is, and whether it is free from contaminants. The problem is that most people do not know how to read one. Here is a complete guide to understanding every section of a cannabis lab report.
Quick Answer: What Is a Certificate of Analysis?
A Certificate of Analysis is a document issued by an accredited laboratory that shows the results of testing performed on a specific batch of cannabis or hemp product. It confirms the cannabinoid potency, terpene profile if tested, and whether the product passes safety tests for pesticides, heavy metals, residual solvents, and microbial contamination. A legitimate COA is specific to a batch number and is issued by a laboratory that is independent of the brand selling the product.
Why COAs Matter
The cannabis and hemp industry operates with limited FDA oversight for most products. Without independent lab testing, there is no reliable way to know whether a product contains the amount of CBD or THC stated on the label, whether it contains more THC than stated (which matters for drug testing and legal compliance), or whether it is free from potentially harmful contaminants like pesticides, heavy metals, and residual processing chemicals.
Research has repeatedly found significant mislabeling in the CBD and cannabis markets. A 2019 study found nearly 70 percent of CBD products were inaccurately labeled. Lab testing is the consumer’s primary protection in an unregulated market.
Section 1: Product and Batch Information
Every legitimate COA will include identifying information at the top: the product name, the batch number or lot number that connects the test results to a specific production run, the sample date or test date, and the laboratory name and contact information.
The batch number is critical. It should match a number on the product packaging. If a brand publishes a single COA for an entire product line without batch-specific testing, that is a red flag. A COA from 2022 does not tell you about the product sitting on a shelf in 2026.
Section 2: Cannabinoid Profile
This is the most scrutinized section and the one that tells you what you are actually consuming in terms of active compounds.
Total THC and Total CBD
Look for Total THC and Total CBD values. These are the most important numbers. Total THC accounts for both Delta 9 THC and THCA (converted by applying a formula: Total THC = Delta 9 THC + 0.877 x THCA). This is important because a product can be low in Delta 9 THC but high in THCA, which converts to THC when heated.
For hemp-derived products to be federally legal, Total THC on a dry weight basis must be at or below 0.3 percent. Some labs report Delta 9 THC alone and some report Total THC. Know which number you are looking at.
CBD and Other Cannabinoids
The reported CBD milligrams per gram (or per serving) should match what the product label claims. If the label says 25mg CBD per gummy and the COA shows a different number, that is either a labeling error or a red flag about quality control.
Other cannabinoids you may see listed: CBG (cannabigerol), CBN (cannabinol), CBC (cannabichromene), CBDV (cannabidivarin), and others. Their presence or absence affects the product’s effect profile through the entourage effect.
Section 3: Terpene Profile
Not all COAs include terpene testing as it costs more than cannabinoid testing. Premium products and full-spectrum products from quality brands often include terpene profiles. This section lists the individual terpenes present and their concentrations, typically in milligrams per gram or as a percentage.
Use this section to understand the character of the product. High myrcene content suggests a more sedating, relaxing product. High limonene suggests a more uplifting profile. High caryophyllene suggests anti-inflammatory potential. This information is more useful for predicting effects than the indica or sativa label.
Section 4: Pesticide Screening
This section tests for the presence of pesticides commonly used in cannabis cultivation. Results are listed as either pass or fail, or as specific concentration levels compared to allowable limits. Each state with a legal cannabis market sets maximum allowable pesticide residue limits.
Common pesticides screened for include myclobutanil (which produces hydrogen cyanide when burned), bifenazate, permethrin, and others. A clean pesticide panel with all results at or below the limit values is what you want to see.
Section 5: Heavy Metals
Cannabis plants are bioaccumulators, meaning they draw heavy metals from the soil in which they grow. This makes heavy metal testing important, particularly for products grown in soil of unknown quality.
The four metals tested are lead, cadmium, arsenic, and mercury. Results are compared against allowable limits set by the state or the USP (United States Pharmacopeia) guidelines. All four should be below their respective limits for a passing result.
Section 6: Residual Solvents
Concentrates produced using solvents (butane, propane, ethanol, CO2) should be tested for residual solvent content. If the extraction process does not properly purge the solvent from the final product, residual chemicals remain in what you consume. This section tests for the presence and concentration of common extraction solvents and compares them to acceptable limits.
This section is most relevant for concentrates, vape cartridges, and tinctures made with solvent extraction. Rosin and dry-sift products produced without solvents may not require this panel.
Section 7: Microbial Contamination
This section screens for harmful bacteria and fungi including E. coli, Salmonella, aspergillus (a common mold), and total yeast and mold counts. All results should show below-limit values for a passing panel.
Microbial contamination testing is particularly important for cannabis that is used by immunocompromised patients including chemotherapy patients, transplant recipients, and HIV-positive individuals, for whom mold and bacterial contamination could cause serious illness.
How to Verify a COA Is Legitimate
Check that the laboratory is accredited. ISO 17025 accreditation is the standard for analytical testing laboratories and most states with legal cannabis require labs to hold this accreditation. The lab’s accreditation status can be verified through the state’s cannabis regulatory website or through the ISO accreditation database.
Verify the batch number on the COA matches your product. QR codes on product labels should link directly to the relevant COA on the lab’s or brand’s website, not just a general lab page.
Be skeptical of in-house testing. A COA issued by the brand’s own lab or by a related entity is not independent third-party testing.
Frequently Asked Questions
Where do I find the COA for my product?
Most brands publish COAs on their website searchable by batch number. Many products now include a QR code on the label that links directly to the relevant COA. If you cannot find a COA, contact the brand directly. If they cannot provide one, that is a significant red flag.
What does it mean if a product passes all tests?
It means the product meets the safety standards for the tested parameters at the tested concentrations. It does not guarantee perfection but it provides meaningful assurance that the product is what it claims to be and free from the most common contaminants.
Do all cannabis products need a COA?
In legal cannabis states, licensed dispensary products are legally required to be tested. Hemp-derived CBD products sold outside the licensed cannabis system are not federally required to have COAs, which is why verifying voluntary third-party testing is so important for CBD products.
What is ISO 17025 accreditation?
It is the international standard for testing and calibration laboratories, confirming that a lab has the technical competence and management systems required to consistently produce valid results. Cannabis testing labs should hold this accreditation for their results to be considered reliable.
Author: Paul Jernigan covers cannabis law, consumer education, and product standards for Ganjly.
Related: Ganjly’s guide to what is CBD and best CBD gummies 2026.
