How to Read COAs (Certificate of Analysis)
Learn to decode lab reports like a pro and spot red flags before you buy CBD products.
Why COAs Matter
A Certificate of Analysis (COA) is a third-party lab report that proves what's actually in your CBD product—including potency, purity, and safety. Never buy CBD without reviewing the COA first.
What is a COA?
A Certificate of Analysis is document issued by an independent, ISO-accredited laboratory that verifies the contents of a CBD product. Reputable brands test every batch and make COAs publicly available (usually via QR code on the product or their website).
What a COA Should Show:
- ✓Cannabinoid Profile: Confirms CBD, THC, and other cannabinoid levels
- ✓Terpene Profile: Shows beneficial terpenes present (optional but valuable)
- ⚠️Contaminant Testing: Verifies product is free from heavy metals, pesticides, residual solvents, and microbial contaminants
- ✓Batch Number & Date: Must match the product batch you're purchasing
- ✓Lab Accreditation: Should be from an ISO 17025 accredited laboratory
Part 1: Cannabinoid Profile
This section shows the actual cannabinoid content. Here's what to look for:
| Cannabinoid | What It Is | What to Look For |
|---|---|---|
| CBD (Cannabidiol) | Primary active cannabinoid | Should match label claim within ±10% |
| THC (Delta-9-THC) | Psychoactive cannabinoid | Isolate: 0% (Non-Detectable) Broad: ND (<0.01%) Full: ≤0.3% |
| CBDA | Raw (acidic) form of CBD | Present in raw/unheated products |
| CBN (Cannabinol) | Degraded form of THC (sedating) | Should be minimal (<1%) in fresh products |
| CBG (Cannabigerol) | "Mother cannabinoid" (antibacterial) | Often 1-2% in full-spectrum products |
Example: Reading CBD & THC Levels
✅ Good Example:
Product Label Claims:
CBD: 1500 mg per 30 mL bottle (50 mg/mL)
THC: Non-Detectable (Isolate)
COA Results (Actual Lab Test):
CBD: 48.7 mg/mL → ✓ PASS (97.4% of claim)
THC: ND (Non-Detectable, <0.01%) → ✓ PASS (matches isolate claim)
❌ Red Flag Example:
Product Label Claims:
CBD: 2000 mg per 30 mL bottle (66.7 mg/mL)
THC: 0% (Broad-Spectrum)
COA Results (Actual Lab Test):
CBD: 28.3 mg/mL → ✗ FAIL (42% of claim—massive underdose!)
THC: 0.42% → ✗ FAIL (over federal limit, not truly broad-spectrum)
Tip: Total CBD = CBD + CBDA (CBDA converts to CBD when heated/vaporized). Some COAs show both separately.
Part 2: Contaminant Testing
This is the SAFETY section. Reputable labs test for four major categories of contaminants:
1. Heavy Metals
Tests for lead (Pb), arsenic (As), cadmium (Cd), and mercury (Hg). These accumulate in soil and can be absorbed by hemp plants.
Acceptable Limits (per California Prop 65):
- • Lead: ≤0.5 ppm (parts per million)
- • Arsenic: ≤0.5 ppm
- • Cadmium: ≤0.4 ppm
- • Mercury: ≤0.1 ppm
2. Pesticides
Tests for 66+ common pesticides. Hemp is a bioaccumulator (absorbs pesticides easily), so this is critical. COA should show "Not Detected" or "ND" for all listed pesticides.
Red flag: If more than 3-5 pesticides are even tested (should test for 50+), the lab may be cutting corners.
3. Residual Solvents
Relevant for concentrates, vapes, and products using CO2 or ethanol extraction. Tests for butane, propane, ethanol, acetone, and other extraction solvents.
Acceptable: Should be "Non-Detectable" or below USP <467> limits.
4. Microbial Contaminants
Tests for harmful bacteria, mold, yeast, and mycotoxins (E. coli, Salmonella, Staph, Aspergillus, etc.).
Acceptable: "Not Detected" or "Absent" for all listed microbes.
⚠️ COA Red Flags - Walk Away!
No Batch Number or Expired COA
The COA must match your exact product batch. If there's no batch number or the COA is older than 6 months, it's not trustworthy.
CBD Content More Than 20% Off Label
Industry standard is ±10% variance. If actual CBD is more than 20% below the label claim, the company is lying about potency.
THC Over 0.3%
Full-spectrum CBD must contain ≤0.3% THC to be federally legal. Anything over is marijuana, not hemp.
Contaminants Detected Above Safe Limits
Any heavy metals, pesticides, or microbes above acceptable limits = UNSAFE. Do not buy.
No Lab Accreditation Listed
COA should clearly state the lab is ISO 17025 accredited. If not listed, the results may not be reliable.
How to Find COAs for Products
QR Code on Product
Most brands print a QR code on the product label. Scan it with your phone to instantly view the COA for that specific batch.
Brand Website
Reputable brands post COAs on product pages or have a dedicated "Lab Results" section. Look up your batch number.
Request from Brand
If COAs aren't publicly available, email the company. Legitimate brands will provide COAs within 24 hours. If they refuse or delay, that's a red flag.
Trust Our Vetting
We personally request and review COAs for every product we recommend. Check our product reviews for verified lab results.
Shop Lab-Tested CBD Products
All products we recommend are third-party tested with COAs showing safe THC levels and no harmful contaminants.
Browse Verified ProductsNote: This content is for educational purposes only and does not constitute medical advice. These statements have not been evaluated by the FDA. See our full disclaimer.