How to read a kratom certificate of analysis

A certificate of analysis, or COA, is the lab report for a batch of product. Most kratom vendors say they lab test. Far fewer publish the actual certificate, and fewer still publish one that covers everything that matters. Here is how to read one, and the gaps to look for.

First, check the basics

• Lab name and accreditation. Look for ISO/IEC 17025. It means the lab’s methods and quality system have been independently audited. A COA from an unnamed or unaccredited lab is a claim, not evidence.
• Batch or lot number. It should match the number printed on your bag. A COA without a batch number, or for a different batch, tells you nothing about what you bought.
• Dates. When was the sample received and when was it tested? A certificate from two years ago says nothing about this year’s harvest.
• Who submitted the sample. If the vendor sent it, they chose which sample to send. That is normal, but it is why we buy anonymously.

The alkaloid section

This is the part most people look at first. Two numbers matter:

• Mitragynine, the main alkaloid, usually reported as a percentage by weight. Natural leaf typically falls in the range of roughly 1% to 2%. Compare it with the label claim: a product labeled 1.6% that measures 1.1% is 31% below what it promised.
• 7-hydroxymitragynine (7-OH), present in natural leaf only in very small amounts, typically well under 0.05%. A much higher number means the product has been concentrated or spiked. See our 7-OH guide.

Watch for units. Some labs report mg/g instead of percent: 15 mg/g is 1.5%.

Heavy metals

Look for lead, arsenic, cadmium and mercury at minimum; nickel is worth having too, since kratom has tested high for it. Results are usually in ppm (parts per million) or µg/g, which are the same thing. Each line should show the measured value, the lab’s limit, and a pass or fail. “ND” means not detected above the lab’s detection limit.

Limits vary between labs and standards, which is why we publish the limits we use alongside every result.

Microbial

This section should include Salmonella and E. coli, which must be absent, plus total yeast and mold and often total aerobic count, reported in CFU/g (colony-forming units per gram). Kratom is a dried agricultural product shipped across the world, so this is where contamination most often shows up.

What is often missing

• Pesticides. Many vendor COAs skip this panel entirely because it is the most expensive.
• Mycotoxins. Also frequently skipped.
• A batch number that matches your bag. One COA for “Red Bali” is not a COA for your Red Bali.
• The full document. A screenshot of the summary line is not a certificate. Ask for the PDF.

How we use COAs

Every KratomSource lab report publishes the full certificate as a PDF, states exactly which limits we applied, and shows the batch number on camera. Where a vendor publishes its own COA for the same batch, we compare the two. Our methodology page has the full process.

Frequently asked questions

What should a kratom COA include?

The lab's name and accreditation, the lot number matching your bag, the test date, and results with limits for mitragynine, 7-hydroxymitragynine, lead, arsenic, cadmium, mercury, salmonella, E. coli and total yeast and mould.

How do I know a kratom COA is real?

Look for the lab's name and report number, then contact the lab to confirm. A screenshot with no lab name, no lot number or no date is not a certificate.

What is a normal mitragynine percentage for kratom powder?

Roughly 1–2% by weight for leaf powder. Much higher numbers suggest an extract or an added alkaloid, and 7-hydroxymitragynine above the natural trace range is a red flag.