Medically Reviewed by
Jason Crawford

Article Last Updated on January 3, 2023

The cannabis plant has numerous benefits due to its main chemical compounds: cannabinoids (tetrahydrocannabinol, cannabidiol, cannabigerol, and others) and terpenes (myrcene, limonene, humulene, caryophyllene, and others). As a result of the increased legalization laws and the medical benefits that cannabis has on users, cannabis use has increased significantly these past years. Cannabis aficionados nowadays have access to a wide variety of cannabis products such as joints, vape pens, bongs and dab rigs, weed edibles, and others. 

With weed’s rise in popularity, we notice that cannabis consumers are often reaching for higher THC strains, and if you’re a newbie in the cannabis world, you may wonder about the average THC levels in weed and what a high THC strain would be. In this article, we’ll give you the answers to the most common questions related to the amount of THC in cannabis, as well as give you a list of some potent cannabis strains.

What Is Considered High THC?

The amount of THC in weed has increased significantly since the 1970s, therefore the weed strains we consider potent today can’t even compare to the strains of the past. To determine whether a strain’s potency is high, the CBD and THC levels are measured. 

Commonly, the THC percentage in weed falls into one of the following categories:

  • Low (0 – 5%);
  • Medium (5 – 10 %);
  • High (10 – 15 %);
  • Very high (15 – 20 %)
  • Extremely high (> 20%).

The average THC level in weed strains in coffee shops in the Netherlands is about 14%. While certain cannabis growers cultivate weed with even higher levels of THC, most users enjoy the medium to high THC strains. If you compare this to hashish found in coffee shops, you’ll notice that hash contains over 21% which is much higher than the average. THC levels can vary based on the grower as well as the strain of weed, so it’s best to do your own research before you commit to a strain.

The Highest THC Percentages in Weed

While it’s rare to see cannabis with THC levels over 25%, the highest THC levels and the most potent weed in the world is in the range between 25-30%. These are often autoflowering weed strains that are cultivated by experienced growers who know how to optimize the THC levels of a cannabis strain. It’s not common to find these specific weed strains in most dispensaries which is why a lot of experienced cannabis users often decide to grow them at home.

Increasing THC Levels When Growing Cannabis

For those cannabis users who want to become cannabis growers and grow weed with high THC levels, there are some steps you can take to improve the potency of your weed and they include:

  • Purchasing quality grow lights and using them in accordance with the plant’s requirements and the growth stage the plant is in.
  • Supplementing with UVB lights during the blooming and flowering stage to increase the THC levels. 
  • Making sure that the roots are well aerated.
  • Optimizing growing conditions and minimizing plant stress.
  • Constantly learning and researching new trends and techniques.

The Effects of High THC Cannabis

While newbie cannabis users won’t appreciate the effects of consuming a potent, THC-rich cannabis strain, seasoned marijuana users or medical marijuana users will appreciate the plethora of effects from these strains. This is generally a result of the increased tolerance to the effects of THC that regular users have compared to newbie users. 

A strain high in THC will give you potent psychoactive effects, a rush of euphoria and energy, and an increase in creativity if you opt for a strain that gives you a head-high. Some people even notice an increase in their appetite after consuming a strain high in THC and these effects can last for several hours. 

Remember that different people can experience different effects when given the same amount of THC, depending on their tolerance levels, BMI, whether or not they’ve eaten before smoking weed, or whether they’re a frequent user or an irregular one. When you consume high THC cannabis, it’s good to remember that the experience can last for several hours, so it’s a good idea to have enough food and water so you don’t feel dehydrated, and you have something to nibble on if you get the munchies.

How Long Does THC Take To Lose Its Potency?

Remember that the quality of your cannabis will degrade over time. This is because light, humidity, and warmth turn THC into its non-psychoactive counterpart cannabinol (CBN). CBN has a lot more in common with CBD than THC, so it’s best to keep your weed in an airtight container away from direct sunlight and heat sources to maintain peak THC levels.

The Best High-THC Cannabis Strains

If you’re looking for some high THC strains to try, below, we’ll give you a list of the strongest strains which will deliver the highest possible THC levels. These weed strains aren’t only high in cannabinoids, but they also contain terpenes such as limonene, caryophyllene, and myrcene that not only give entourage effects when you consume them, but they also enrich the cannabis strain with a unique variety of aromas. Here are some of the most potent strains you can find in well-equipped dispensaries and remember that the THC levels in each strain can vary from producer to producer. Just keep in mind that if you’re a beginner, you should definitely go for a low THC strain and avoid these altogether, or until you’ve built up a tolerance to cannabis.

Bruce Banner

Average THC levels: 23%

One of the highest THC strains on the weed market is definitely Bruce Banner. With a terpene profile of myrcene, caryophyllene, and limonene, this hybrid with an astonishing THC content was rated the strongest strain by High Times back in 2014. A combination of OG Kush and Strawberry Diesel, this weed strain will give you an uplifting and psychoactive high which will relax your body completely. 

Kosher Kush

Average THC levels: 20%

The next high THC strain on our list is Kosher Kush, a strain that won the Cannabis Cup back in 2010 and users have been loving it ever since. The strain is a tranquilizing Indica that is great for experienced users. When it comes to terpene content, this strain contains a mix of myrcene, limonene, caryophyllene, and depending on the producer, the THC levels can be even higher.

Original Glue

Average THC levels: 20%

This multiple Cannabis Cup award winner offers a potent high that will leave you in a couch-lock position for a huge chunk of your evening. It contains a variety of terpenes among which the primary terpenes are myrcene, limonene, caryophyllene, and others. This potent weed strain got its name for its resinous sticky buds, and it sure lives up to that name.

Ghost OG

Average THC levels: 20%

A strain that is closely related to the original OG Kush is Ghost OG. This potent strain has a symphony of powerful terpenes such as myrcene, limonene, and caryophyllene that contribute to the entourage effects of the strain. The resinous strain gives users a euphoric and powerful high which will relax even the most tensed person.


Average THC levels: 19%

We can’t conclude this list of weed strains without mentioning Chemdog. This potent strain is the reason why a lot of users keep coming back to it over and over. Its terpene profile includes caryophyllene, myrcene, limonene, and other terpenes that give this strain an unforgettable aroma, but also an energetic and euphoric high that can boost your creativity.

Final Thoughts

Being informed about the latest news on the cannabis market is essential if you’re on the lookout for new cannabis strains with high THC levels as cannabis growers are always challenged to improve the cannabinoid content of their product. With regards to weed potency, any strain that’s over 20% THC is considered a high THC cannabis strain intended for use by people who are consuming marijuana medicinally, or seasoned cannabis lovers with a high tolerance to THC. 

For more suggestions on weed strains you can try that have high levels of THC, check out our guide on the subject.

A passionate advocate for the benefits of cannabis. Fraser Horton, who has a background in botany and a strong love of nature, has spent years researching how cannabis affects the body and mind. He established Leaf Nation in 2020, where he has devoted himself to educating people about the legalisation of marijuana and its safe and responsible use. Fraser is committed to highlighting cannabis’ potential for improving wellness and working to dispel the stigma associated with its use.


The information presented on this page is provided as a public service to aid in education and is derived from sources believed to be reliable. Readers are responsible for making their own assessment of the topics discussed here. In no event shall Leaf Nation be held reliable for any injury, loss or damage that could happen if using or abusing drugs.