Wondering How Many Grams of THC Are in an Ounce?

Introduction: Why THC Measurements Matter in 2025

In 2025, cannabis is more potent and diverse than ever, making it critical to understand how many grams of THC are in an ounce — especially for medical patients, recreational users, and home chefs alike. Whether you’re rolling joints, making edibles, or exploring concentrates, precise THC knowledge ensures both safe enjoyment and compliance with the law.

What Is THC? 

Understanding THC Potency

THC, or tetrahydrocannabinol, is the main psychoactive compound in cannabis that causes the “high.” Unlike CBD, which is non-intoxicating, THC directly affects mood, perception, and sensation.

THC in Cannabis Flower vs. Extracts

In cannabis flower, THC is measured as a percentage of the dry weight — typically ranging from 10% to 30%. In extracts and concentrates, THC levels can skyrocket to 60%-90% or higher.

Basic Cannabis Weight Conversions

Ounces to Grams: The Standard Math

One ounce equals 28.35 grams. This is a universal conversion used in cannabis measurements worldwide.

Why Grams Matter in THC Calculations

Because THC is measured as a percentage, you need to know the total dry weight (in grams) to calculate how many grams of THC are present.

Average THC Percentage in Cannabis

Cannabis strains can vary widely in THC content. Here’s a quick breakdown:

The THC percentage tells you how much of each gram is pure THC.

Calculating THC in an Ounce of Weed

Let’s do the math. Use this simple formula:

$$\text{THC (g)} = \text{Weight (g)} \times \left(\frac{\text{THC \%}}{100}\right)$$

Example:
Let’s say you have 1 ounce (28g) of cannabis with 20% THC.

$$\text{THC} = 28 \times \frac{20}{100} = 5.6\text{ grams of THC}$$

💡 THC Content by Potency:

Factors That Affect THC Content

Several things can affect the real amount of THC you get:

1. Strain genetics – Indica, sativa, and hybrids have different profiles.

2. Curing & drying process – Poor curing can degrade THC.

3. Storage conditions – Light, air, and moisture degrade THC over time.

4. Lab testing accuracy – Not all dispensary data is standardized.

Comparing Flower, Concentrates, and Edibles

THC in Concentrates (Waxes, Oils, Shatter)

In concentrates, THC percentages can hit 70%-90%. This means one gram of concentrate might contain 0.7g to 0.9g of THC, far exceeding the flower’s potency.

THC in Edibles: Why It’s Tricky

When making edibles, not all THC converts during cooking. Decarboxylation, fat absorption, and preparation methods can reduce effective THC by 20-30%.

Common Misconceptions About THC Measurements

• Myth: All ounces of cannabis have the same THC.
  Truth: Potency varies widely by strain and batch.

• Myth: Smoking an ounce equals ingesting all the THC.
  Truth: Combustion losses and bioavailability reduce the total.

Final Thoughts

So, how many grams of THC are in an ounce? The answer depends on the potency of your weed, but on average, you're looking at 2.8 to 8.4 grams of THC per ounce. Knowing this can help you dose smarter, spend better, and truly understand what you're consuming.

FAQs

Q: Is 1 gram of THC a lot?
A: Yes! That’s equivalent to around 5–10 strong edibles. Most beginners only need 5–10 mg of THC per dose.

Q: Does smoking destroy some THC?
A: Yes, combustion can destroy up to 40–50% of THC due to heat loss.

Q: Can I extract pure THC from an ounce?
A: Yes, through methods like distillation or CO₂ extraction, but it's complex and requires lab-grade equipment.