Testing for THC

Is there any relatively inexpensive way to test for actual THC content? All of the ‘testers’ I have found on the web are for testing job-related urine samples. These are simple positive/negative results, not an accurate measurement.

A half-century ago, I was a chemistry major and lab tech at a big-city hospital. I was used to using very sophisticated - and expensive - analysis equipment. This year, I grew four different strains, and I am curious about actual potency. (Yeah, they are all very good…) But I’d like to know just how good, which lived up to the hype, and I don’t happen to have ten grand lying around for a good, used gas chromatograph.

This might be a good business opportunity - if you happen to have a spare ten grand…


Hey @Newt is this the brand you use?

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Google THC Potency test
keep the 10K

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It is. And if you get it from tcheck dot me, you can use code Check15, for 15% off.


Mind you, there are two versions of the T-Check 2 kit. The $300 one does clear extractions, while the $400 does buds.( I think that the difference is the nifty grams scale.) When doing a quantitative analysis, you need to know precisely the volume - or weight - of the sample being tested.

I recall a little test kit for weed circa 1969. It was in a small plastic box, much like a soil or pH test kit, in that it was colormetric. It included a solvent, a reagent and a stain, and could tell you if your stash was great, or Mexican ditch weed… or oregano. With full legalization and retail sales, I can see that an independent testing service might be a profitable side-hustle.

The add-on adds:

  • – Scale
  • – 1 100 mL bottle of reagent
  • – 10 .22um filters
  • – 1 10 mL syringes
  • – 10 1 mL syringes
  • – 3 sample containers
  • – 3 concentrate spoons
  • – 1 Swizzle stick
  • – 2 AAA batteries
  • – 1 Getting Started Guide

But all you really need is a precise scale, a syringe, and filter and re-agent grade 99.9& isopropyl, Nothing in the expansion kit is special, and can be had from the place that used to be an on-line book store. :wink:

(Which is where I get my consumables - reagent, syringes, and filters)

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I am a retired chemist myself. I have been thinking about THC testing myself and scour the reused equipment sites. Best to you.


Where is this used equipment site :thinking::crazy_face:

I don’t smoke so I just ask my smoker friends to test it for me.so far no complaints.
Wish I did know the thc content of my grows.


LabX is one but there are also government and state auction sites.

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I’ve done several web searches on THC potency testing, all of which returned kits and such. None mentioned the actual methodology. The T-Check 2 appears to use a colorimeter; the lower priced one is for extracts, which can work by volume. The higher priced one is for actual weed, with filter paper included after solvent extraction. I could probably build my own - if I knew what solvents or reagents were involved. Newt mentioned 99% isopropanol which would be the solvent. In the hospital, we used to use USP-grade ethanol by the drum. 95% was used for rinsing lab glassware; the 100% (200 proof) ‘absolute’ ethanol was used as a solvent. Untaxed, it was cheaper than milk…


I just take mine down to the local hydroponic shop to have tested. Typically charge 20 bucks but I just threw them a little handful of bud for helping me through my first grow anyway. They didn’t charge me a dime .

I test mine the old fashion way. No numbers i use more of a 1 to 10 scale of my personal thoughts on smell, taste and buzz. Plus i usually ask a couple friends their opinions. So far the best stuff ive grown i would give an 8. Always room for improvement.


By all means, get one of these testers if you want. But it may be money not well spent.

All testing equipment needs to either have reference to a constant (like the speed of light for example) or be calibrated (ie: compared) to a known reference point - another tester or material of known spec. The later is typically how you would calibrate your PH pen.

I don’t know the specifics of these testers but unless they come with a calibration cert or some sort of reputable endorsement, the number it gives could mean anything.

Here is a better bang for your buck

Excellent… How much was the kit? A half century ago when I was a lab tech in a big hospital, I typically used electrophoresis to measure serum proteins, hemoglobin types and cholesterol levels. Spent a full summer doing research using chromatography to predict Schizophrenia by using patterns of amino acids. It was pretty cool, except for the solvent, pyridine, which is the nastiest-smelling stuff on the planet.

I’ll check out the kit… Thanks

About $140 for the cheapest kit… But the technique is very similar as to what I used to do sorting amino acids, except it used plain, cheap filter paper sheets. It was almost psychedelic when ninhydrin was sprayed on the dried filter paper. Ohhh…,the colors… :wink:

I suggest you read the review. @emgoldslo had suggested other people get better quality items themselves and build their own kit, then get the things needed from the supplier that were more proprietary