How to calculate CBD content

by Apoorva Shivankar, M.D

CBD calculation guide for buying the best product

best CBD products

A right amount of CBD at a right time is essential for an apt effect. Cannabis is a double-edged sword. Lesser the dose and you label it ineffective whereas higher the dose and you experience the undesirable effects. We also admit that it’s not an easy job to find the right one when millions of similar products with different concentrations and forms are available out there in the market. So, here we are to get the big question sorted.

How do you calculate CBD?

‘Effective doses are not the same for everyone, they even differ in a single individual as per the purpose they are being used for.’

Why? Because they vary with:

  • weight
  • age
  • tolerance to CBD
  • body chemistry
  • severity of condition
  • type and form of CBD used.

To simplify, one should decide how much CBD (strength) is needed as per the condition to be treated and then match it with the dosage required as per individual’s parameter.

So how will you calculate CBD STRENGTH needed?

Follow the Universal law which states,

More severity demands more strength.’

  • General conditions such as weight loss, appetite, mood, cosmetics, etc. can be settled with low to medium strength.

  • Health concerns like sleep disorders, anxiety, depression, migraine, chronic pain, etc. mostly work well with medium to high strengths.

  • Severe medical conditions such as epilepsy, severe arthritis, severe neuropathic pains, inflammatory bowel disease, etc. may need a very high strength of CBD to bring the desired relief.

Now match these with your most significant parameter - weight. How?

If you need a

  • High strength CBD effect:

consume around 12-14mg/10 kg or 6-7mg/ 10 pounds body weight.

  • Medium strength:

take around 6-8mg/10 kg or 3-4mg/10 pounds.

  • For low strength:

2mg/10kg or 1mg/ 10pound should suffice. 

Thus, the calculation:

Desired strength factor x body weight = required amount.


If you are 50 kgs looking for a CBD hemp oil to soothe your anxiety,

start with medium strength CBD oil having 0.6 x 50 = 30 mg of CBD content.

I hope this calculation takes you one step closer to your cannabis product.

Now you have an idea about how much CBD amount you need but then how will you obtain these desired milligrams from a bottle of CBD Oil?

Simply check the labels and some more mathematics to find out how to calculate the CBD hemp content.

A good CBD hemp oil bottle label indicates the cannabidiol content in mg or %. Dividing the total mg of CBD content by the total volume of oil gives you mg of CBD per ml and then you can determine the number of ml to be consumed accordingly.

Taking the above example ahead, if you need 30mg of CBD/serving from a 30ml oil bottle having 300mg of total CBD content,

Step 1: Calculate CBD content per ml of CBD oil by = 300 divided by 30= 10mg/ml

Step 2: So10mg is present in 1ml, then 30mg will be in= 30/10= 3ml

Result: you should take 3ml/serving to get your desired 30mg of CBD.

For the sake of ease of administration, hemp oil is usually dispersed with dropper (mostly 1ml dropper) wherein 1ml corresponds to around 20drops. Accordingly, the number of drops can be adjusted. For example, 3ml = 60drops.

But what if the label expresses CBD content in percentage in order to depict purity?

(A confusion created due to lack of standardisation over label contents).

No worries, just keep 2 points in mind:

  • 1gram = 1000mg

If you have 20% CBD it means 20mg per 100gms and thus 200mg per 1000mg.

So, 20% means 200mg of CBD in 1ml CBD oil.

  • Formula:

Bottle volume (ml) x CBD percentage = CBD content in grams.

Bottle volume (ml) x CBD percentage x 1000 = CBD content in milligrams. 


If a 10ml bottle says 10%

Amount of CBD (mg) = 10 x 10/100 x 1000= 1000mg.

Ready for the test?

What percentage is 500mg CBD oil?

Answer: 50% (considering the volume as 1ml)

1 x ? / 100 x 1000 = 500, therefore ? = 500/1000 x 100, resultant ? = 50

Similarly, 500mg means 5% if volume is10ml.

So, if you are a mathematics lover, enjoy the calculations but….

If you are scared of it, don’t be intimidated; edibles like gummies with pre-measured CBD content work for you. No calculations, just read the label and enjoy.

Unfortunate truth of this story is, though all these calculations clarify your confusion regarding CBD content and dosage, there are many factors yet to be considered in order to fetch the best possible outcome.

One such factor is QUALITY

We all know that a poor-quality product is just a waste of money even if it is present in 100% concentration. So, apart from the strength needed and amount of CBD available we should always check for the product quality. 

How do you measure CBD quality?

By attending the following points:

  • Where and how the hemp plant is grown:

Hemp plant grown naturally in United States within USDA (United States Department of Agriculture) - compliant state regulatory norms of cultivation should be preferred. The reason being hemp plants easily absorb almost everything from the soil irrespective of good or bad. 

Farms under USDA norms are regularly checked for
heavy metals, petroleum, toxic chemicals, bacteria, fungus, solvent residue, or any other foreign matter.

  • Mode of CBD extraction:

Supercritical CO or ethanol CBD extraction methods leave no harmful residues post - extraction and hence, yield better CBD oil than those extracted using chemicals like propane, butane, pentane, or hexane.

  • THC concentration should not be more than 0.3%:

Inferior quality CBD products can have a higher THC level making it both psychoactive and illegal.

  • Cannabinoid profile:

Of the 3 forms available - isolate, broad-spectrum and full-spectrum, full-spectrum works the best as it carries other cannabinoids, flavonoids, and terpenes too along with CBD and they all complement each other to get the best possible final outcome of CBD.

  • Should be well-labelled:

A good label describing the CBD concentration, ingredients, purity, mode of extraction, etc. imparts transparency and confidence towards the quality of the product.

  • Certificate of Analysis (COA):

In-home and third-party testing verifies the quality. COA is a written guarantee regarding the CBD content, purity, and the truthfulness of the product given by a laboratory having no stake in the product.

  • Information about carrier oils:

MCT oils like coconut oil or hemp seed oil or olive oil nurture the quality of CBD products in contrast to cheap oils like grapeseed oil.

  • Never forget to check the reviews uploaded on the site by people who use CBD for the same purpose.

Now with the knowledge of how to select great quality products with desired CBD concentration, I hope you will be able to eliminate a few more confusing products from your selection list.


Ignoring the concept of BIOAVAILABILITY can be a big blunder while calculating CBD dosage.

A poor bioavailability can easily rip off all your calculation efforts. What’s the use of consuming the best quality CBD product in a well-calculated dosage if it is not being absorbed or utilized properly?

The bioavailability of orally consumed CBD products like hemp oils, capsules, candies, and gummies is very low as they have to pass through the entire digestive system before getting absorbed losing a large proportion in the way. The answer to this is the newer liposomal or nano-emulsifying formulations which have a significant fast absorption and minimal loss.

Sublingual CBD tinctures, topical and vaping forms have much better bioavailability with the maximum for vapours as they are directly absorbed.

So, while calculating the dosage always remember,

‘Lower the bioavailability of products, higher is the dosage required for the same effect.’

Last but not least is the POTENCY of CBD product.

No, potency and strength are not the same.

Potency is the amount of the drug required to actually produce a defined effect (lower amount = more potent)

whereas strength is the concentration of the drug present in a formulation.

In fact, potency is a combination of strength, form, delivery mode and product quality.

  • Maximum calculated strength


  • Full-spectrum CBD product


  • Liposomal or CBD tincture or inhalational mode of delivery- best bioavailability


  • Supreme quality


Highest potency (maximum/best effect in lowest possible doses.)


Finally, to calculate CBD content and dosage is a game of permutation and combination of all the above-mentioned factors and need a lot of trial-and-error in the beginning.

Our advice is, always use high-quality products, calculate the best possible dose range required, and follow the GOLDEN RULE of CBD which says,

‘Start with the minimal calculated dose, give time to see the effect, gradually work your way up till you get your desired results.’