How to test THC / CBD (cannabinoids): reduce risk by using a cannabis test kit to check it for adulterants. Cannabis products come in all kinds of forms and can’t be reliably identified by appearence. To test THC and CBD use the reagent test Cannabis in single-use or multiple-use test kit. Reagent tests are simple chemicals that indicate presence of a substance by reacting with different color change to different substances. To test you need just 1 drop of a reagent and a small sample, about this big -> To detect all ingredients and estimate potency it’s required to use the additional Cannabinoid test kitTo detect fentanyl or test for fentanyl analogs use the fentanyl test strips.

To detect all ingredients and estimate potency it’s required to use the Cannabinoid test kitA positive or negative test result does not indicate if the substance is safe. No substance is 100% safe.

How can I test cannabis?

Short instructions:

BEFORE using a cannabis test kit
  • it’s RECOMMENDED to record the reaction to compare later.
  • if testing an extract use a smaller sample.
Cannabis testing instructions
AFTER using a cannabis test kit
  • Wash testing surface under running water.

For full instructions scroll further down below.

VIDEO & RESULTS Watch how to test cannabis

TL;DR: Below is a quick cheat sheet how to use the Cannabis Reagent Test Kit and further down you can check out more detailed guide including how to test all cannabinoids and measure potency using the Cannabinoid PRO Test. Use the reagent test results chart to see how to use the Cannabis reagent, the TLC Cannabinoid dye and what are the expected results.

All cannabis test results:

Cannabinoid Cannabis reagent TLC dye
THC Blue Pink / Red
Δ8-THC Blue  
THCA Blue  
THCV Blue Pink / Red
THCVA Blue  
CBD Pink Orange
CBDA Purple  
CBDV Pink  
CBDVA Purple  
CBL Blue  
CBLA Blue/Green  
CBG Pink Light orange
CBGA Pink  
CBN Blue Pink / Red
CBNA Blue  
CBV Pink  
CBC Blue Pink / Red


Cannabinoid dye test results

(click to view or scroll down for video)

Cannabis test did not react as expected? Watch out!
All test results are available in our instructions and the TestDrugs app.

STEP ONE How to identify THC or CBD?

What test kit do I need to test cannabinoids (cannabis products)?


Reagents can be divided into primary and secondary. Primary reagents react with the expected substance while secondary produce a vibrant color change with an adulterant. Unfortunately due to the complex nature of samples such as flowers or cookies there are no reliable secondary reagents able to identify all mixed-in synthetic cannabinoids. To detect those test for CBD – if the sample produces strong effects, but is CBD dominant, it’s most likely adulterated. Here are a few key notes:

  • Cannabis – primary reagent test for all cannabis products, tells apart THC dominant (blue) and CBD dominant (purple) samples
  • Cannabinoid TLC dye – optional add-on to the TLC Cannabinoid test kit for identification of all common cannabinoids; toxic
  • Cannabinoid TLC kit – thin layer chromatography test kit able to identify all present cannabinoids and estimate their potency

Cannabis reagent is the main test for all cannabis products and produces a quick blue color change with THC, and purple with CBD dominant samples, without the need to prepare a sample in any special way before testing. Cannabinoid TLC test kit is the recommended follow-up test to discover full cannabinoid profile and estimate potency, however it requires reagent tests to identify the detected substances. To identify all of the cannabinoids detected with TLC it’s required to use the TLC Cannabinoid dye.

Marquis reagent tests for MDMA and 2C-B

CBD and THC test results using the Cannabis reagent

How to use the Cannabis reagent test
  • Consider that if you are testing plant matter but the sample does not resemble a flower, it’s probably adulterated.
  • Test as small sample as possible and only try more if you are not getting a conclusive result.
  • Check the Cannabis test kit test results:
    • if testing a THC dominant sample the color of the reaction should be blue. It can look pink or purple for a few seconds before turning dark blue.
    • if testing a CBD dominant sample, the resulting color change should be to pink or purple over 30-60 seconds and fades with time.

STEP TWO How to test cannabinoid potency and purity?

According to and more and more cannabis samples turn out to be CBD flower laced with synthetic cannabinoids.

Try the Cannabis reagent. It detects if a sample contains more THC or CBD, which makes it a great screening test, especially for synthetic cannabinoids.

Unfortunately due to the complex nature of samples like a flower or a cookie there are no reliable tests able to positively identify all mixed-in synthetic cannabinoids. To detect adulterants test the amount of THC – if a sample produces strong effects, but is CBD dominant, it’s most likely adulterated.

How to test THC / CBD?

Next choose the cannabinoid potency test kit. It enables you to separate a sample into different substances and estimate quantity, however still requires reagent tests to identify the detected substances. To discover full cannabinoid profile and quantity pair the TLC (Thin Layer Chromatography) Cannabinoid Test Kit with the Cannabis reagent or the TLC Cannabis dye. TLC tests alone don’t identify substances and are best paired with 1-2 reagent tests.

About the TLC Cannabinoid Test:
  • Qualitative: One spot indicates a pure substance. TLC test works by separating substances present in a sample in order to reagent test them individually.  You can also use an already confirmed sample for reference – if both compounds show up at the same height on the TLC “card” that indicates they are the same substance.
  • Semi-quantitative: TLC also helps estimate quantity (potency). The bigger the size of the detected spot, the bigger the amount of measured substance. Note that different substances need different calibrated rulers.
Sample 1 and 2 contain similar CBD:THC ratio

TLC Cannabinoid PRO Test results

Sample 1 and 2 contain similar CBD:THC ratio

For full TLC (Thin Layer Chromatography) instructions read our guide how to test drugs purity.

FENTANYL How to detect fentanyl?

What is fentanyl?

Fentanyl is an extremely potent and dangerous synthetic opioid, often mixed in street drugs and deadly.

BEFORE using a fentanyl test strip
  • It’s RECOMMENDED to test each and every dose. Because of extreme potency (microgram range) fentanyl is never evenly mixed in. One part of a baggie can be fentanyl free and another lethal.
How to test THC / CBD?
How to test fentanyl spice / flowers / hash with a fentanyl test strip?
  • Dissolve 100 mg in at least 125 ml of water (half a cup or at least 1 mg/ml).
  • Grab a test strip and insert the white end into the liquid, no higher than the thick line.
  • Wait until liquid starts visibly moving up the test strip (up to 15 seconds).
  • Put the test strip away on a flat dry surface and read the result in 2 minutes.
  • Check test strip result: a single line confirms the presence of fentanyl, while two lines (even faint) rule it out.

Fentanyl test did not react as indicated? Watch out!
All test results are available in our instructions and the TestDrugs app.

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FAQ Frequently Asked Questions

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