THC Content In A Joint: Everything You Need To Know

A 1g joint at 20% THC contains 200mg total, but you only absorb 100mg. Learn the simple formula that converts any flower percentage to actual mg's.

THC Content In A Joint: Everything You Need To Know

Written by Sipho Sam

August 21st, 2025

Here's the answer you're looking for: A 1-gram joint at 20% THC contains 200mg total, but you only absorb about 100mg.

The rest goes up in smoke – literally.

If you've been confused trying to convert the percentage on your flower label into the milligrams you understand from edibles, you're not alone.

That 25% THC label might as well be written in another language when you're trying to figure out if it'll deliver your perfect high or leave you uncomfortably blazed.

Good news: A simple formula works for any joint, and we'll show you exactly how to use it.

We'll use Mood's lab-tested prerolls as examples throughout, since their consistent sizing and transparent testing make the math crystal clear.

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Table of Contents

  • A 1 Gram Joint Contains 200mg of THC But You Only Absorb Half

  • Converting Flower Percentages to Actual Milligrams

  • Where Half Your THC Goes When You Light Up

  • Why Your Joint Needs 10 Times More THC Than an Edible

  • Each Puff Delivers About 5mg of THC to Your System

  • Today's 25% THC Flower Versus Yesterday's 5% Weed

  • What Happens If You Smoke Too Much THC

  • Your Personal THC Math Will Be Different

  • The THC Formula That Works for Any Joint

A 1 Gram Joint Contains 200mg of THC But You Only Absorb Half

Let's cut through the confusion with real numbers: when you pick up a joint labeled 20% THC that weighs 1 gram, you're holding 200mg of THC because the math is refreshingly simple – weight × percentage = total mg.

Take Mood's Kush Mintz prerolls as an example — at around 28% THCa, that one-gram joint contains 280mg on paper.

Once heated, THCa becomes more potent, converting to about 246mg of active THC.

But here's the kicker – you'll only absorb roughly 125mg of that into your bloodstream.

The average joint contains anywhere from 16mg to 64mg of THC, depending on size and potency.

But those are typically smaller 0.32g joints.

With Mood's consistent 1-gram sizing, you're getting significantly more – which is exactly why understanding absorption matters.

Converting Flower Percentages to Actual Milligrams

Once you know the trick, the conversion that trips everyone up is straightforward: since 1 gram equals 1000 milligrams, calculating THC content means multiplying that percentage by 1000.

So 20% of 1000mg equals 200mg of THC.

For hemp products like THCa flower, there's one extra step.

THCa becomes more potent when heated, yielding about 87.7% of its weight as active THC.

Don't worry about memorizing that number – know that a 25% THCa label means roughly 22% THC after you light up.

What makes Mood's COA numbers so helpful is their transparency – every batch comes with lab results showing exact percentages, taking the guesswork out of your calculations.

Where Half Your THC Goes When You Light Up

Here's why that 200mg joint doesn't hit like 200mg of edibles: combustion is incredibly wasteful.

Between sidestream smoke drifting away, incomplete burning, and what you exhale, you lose 60-63% of your THC before it ever reaches your bloodstream.

Studies show you absorb only 20-27% of the THC in your joint.

The rest is lost to the atmosphere.

Even ultra-potent options like THCa moonrocks at 38.04% THCa follow this same rule – you're getting about half of what's on the label.

This isn't a quality issue – it's just how combustion works.

Your joint is constantly burning, sending smoke into the air whether you're actively puffing or not.

Add in what you breathe out, and those losses pile up fast.

Why Your Joint Needs 10 Times More THC Than an Edible

Ever wonder why a 10mg gummy rocks your world, but you can smoke way more without the same intensity?

It's all about how your body processes THC differently when you eat it versus smoke it.

When you eat Mood's 15mg THC gummies, your liver transforms THC into a more potent form that hits harder and lasts longer.

Smoking delivers THC directly to your bloodstream through your lungs, creating a faster but lighter effect that fades within a few hours.

The community rule of thumb holds true: 10mg eaten feels like 100mg smoked.

That's why someone who gets perfectly lifted from a single gummy might comfortably smoke an entire joint containing 200mg without overdoing it.

Each Puff Delivers About 5mg of THC to Your System

Breaking it down by puffs makes finding your perfect amount much more manageable: a typical 1-gram joint gives you 15-20 good hits.

If you're absorbing 100mg total from that joint, you're getting roughly 5mg per puff.

For higher potency options, each hit delivers more.

A single puff from a 0.5g joint at 30% THC can deliver 7.5-15mg to your system.

That's why Mood's consistent 1g prerolls make puff counting so reliable – you know exactly what you're working with.

New to cannabis? Start with 2-3 puffs and wait 10 minutes. You can always smoke more, but you can't smoke less once it's in your system.

Today's 25% THC Flower Versus Yesterday's 5% Weed

Cannabis has gotten significantly stronger over the decades.

In the 1980s, average flower tested around 3-5% THC. By the 1990s, it crept up to 5%.

Today's average sits between 15-20%, with premium options pushing past 30%.

Mood's top shelf THCa flower range of 24-32% represents the modern standard – potent but not extreme.

This isn't about creating the strongest possible product. It's about consistency and giving you options that match your tolerance.

One thing to remember: THC degrades over time, losing about 17% potency per year.

That's why Mood includes humidity packs with its products — keeping your flower fresh means keeping those percentages accurate.

What Happens If You Smoke Too Much THC

Let's be real – sometimes you miscalculate.

While you can't dangerously overdose on cannabis, too much THC can leave you feeling uncomfortable.

Common experiences include feeling uneasy, having a dry mouth, and experiencing that "too high" sensation when time seems to slow down.

The good news? These feelings are temporary and typically fade within 2-3 hours after smoking. Stay hydrated, find a comfortable spot, and remind yourself it will pass.

Some people find that CBD can help balance out an uncomfortable high.

Quick note for those with workplace concerns: Yes, hemp-derived THCa products will show up on drug tests.

Once heated, THCa becomes regular THC as far as testing is concerned, so plan accordingly.

Your Personal THC Math Will Be Different

Everything we've covered gives you the baseline, but your experience will vary based on several factors.

Daily smokers might need 15mg per puff to feel anything, while someone who partakes monthly might feel 5mg strongly.

Your metabolism, body weight, and even what you've eaten can affect how THC hits you.

Smoking technique matters too – deep inhales and holding hits deliver more THC than quick puffs.

This variability is exactly why products with consistent potency like Mood's lab-tested prerolls help so much.

When the product is reliable, you can dial in your perfect dose through experience.

The THC Formula That Works for Any Joint

Here's your takeaway formula that works every time:

(Weight in mg × THC%) ÷ 2 ÷ number of puffs = mg per puff

Let's run through one final example using Mood's transparent COA data.

  • You've got a 1-gram preroll at 28% THCa.

  • That's 1000mg × 0.28 = 280mg total.

  • After heating, you get 246mg of active THC.

  • Cut that in half for absorption: 123mg.

  • Divide by 20 puffs; you're looking at about 6mg per hit.

With this knowledge, you can evaluate any joint, read any label, and make informed decisions about your consumption.

You've got the tools – now go forth and enjoy responsibly. Make it easier for yourself and start at the Mood Shop today.

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