The most useful number on any cannabis package is total THC in milligrams per dose, and that is the top pick for judging potency before you buy. Percentages describe concentration; milligrams describe what actually reaches you, and milligrams are the only figure you can line up across a joint, a vape puff, and a gummy. The criteria behind that pick: the number has to appear on a state-regulated label, it has to stay comparable across product types, and it has to scale with your own tolerance. What follows walks through each product category so you know what to read on the menu and what to ask at the counter.

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Why dose beats percentage

A flower label reading 28 percent THC and an edible label reading 10 mg THC are not competing claims. The flower figure means roughly 28 percent of the plant material's dry weight is THC and the acids that convert to THC when heated. The edible figure means the whole serving contains 10 mg. One gram of that flower holds about 280 mg of THC locked in the plant material, and you absorb only a share of it when you smoke or vape. A single 10 mg gummy delivers close to all 10 mg because it passes through your digestive system. Same plant, very different exposure.

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That gap is why frequent shoppers stop buying on percentage alone. A 22 percent flower that you smoke in three puffs can land harder than a 32 percent flower you vape once, and both can be gentler than a 5 mg mint eaten on an empty stomach.

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Flower: percentage plus one multiplication

Flower is the easiest format to reason about because the math is public. Multiply the THC percentage by the package weight to get total milligrams, then decide how much of that gram you plan to consume in a sitting.

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Pros

  • Package weight and THC percentage are both printed, so you can estimate total THC yourself.
  • Effects arrive within minutes, which lets you stop before you overshoot.
  • Small amounts are easy to measure out and easy to repeat.
  • Lower-percentage flower gives you more room to adjust puff by puff.

Cons

  • Combustion destroys some THC, and how much you absorb depends on inhalation depth and breath hold.
  • Percentages above roughly 30 are uncommon, and small lab variations can account for a few points of difference.
  • Very high testing numbers do not automatically mean a better experience, and shelf placement often tracks the number.

Best for: someone who wants fast feedback and fine control over each puff, including people who are new to cannabis and want to start with one or two small hits.

Vape cartridges and concentrates

Concentrates and cartridge oil commonly test in the 70 to 90 percent THC range. A single draw can deliver several milligrams without any obvious cue that you just took a meaningful dose.

Pros

  • Fast onset, similar to flower.
  • No smoke and very little odor, which matters in apartments and shared spaces.
  • Small physical volume, so a little lasts a long time.

Cons

  • A puff is hard to measure, so tracking your actual intake is guesswork.
  • Tolerance climbs quickly with daily cartridge use.
  • Potency is concentrated enough that overshooting is easy, especially with a device you have not used before.

Best for: experienced consumers who want quick onset without smoking. This is not the format to try first.

Edibles: the milligram is the whole story

Edibles are dosed, not estimated. Ten milligrams is a common single serving in legal markets, and 2.5 to 5 mg is a common starting point for people with little or no tolerance. Onset usually runs 30 minutes to 2 hours, and effects can last 4 to 6 hours or longer.

Pros

  • Precise serving sizes printed on the package, and many products are scored for splitting.
  • No inhalation, which suits people with lung concerns.
  • Long, steady effect once it starts.

Cons

  • Slow onset tempts people to take a second serving too soon.
  • Once it hits, you cannot dial it back down, and the duration is long.
  • Digestion converts THC into a metabolite that some people find noticeably stronger than inhaled THC.

Best for: anyone who wants a long, even effect and can wait an hour without redosing. Keep a note of what you took and when.

CBD, CBG, and other cannabinoids

CBD does not cancel THC, but many people report a calmer experience with balanced ratio products. The research on that is mixed, so treat it as a preference rather than a switch. CBG, CBN, and THCV appear on some state labels, and the clinical evidence for them is thin.

Pros

  • Balanced products can feel gentler for people who find THC alone edgy.
  • Ratios are printed on regulated labels, so you can compare products directly.

Cons

  • A high CBD number is not a guarantee that THC will feel mild.
  • Minor cannabinoid content is often too low to matter at a 10 mg dose.
  • Balanced and minor-cannabinoid products usually sit in a higher price tier.

Best for: someone easing in who wants a milder experience, or a regular consumer looking for a different feel rather than more strength.

Terpenes and the entourage effect

Terpenes such as myrcene, limonene, and pinene drive aroma and flavor. The idea that they also shape the high is plausible and widely discussed, but clinical evidence is limited, and terpene percentages are not a reliable potency predictor.

Pros

  • Terpene profiles are a reasonable way to shop for taste and aroma.
  • Some consumers find that familiar profiles feel more consistent to them.

Cons

  • Terpene content tells you nothing about how much THC you are taking.
  • Testing methods and reporting vary, so numbers are hard to compare across brands.
  • Very high terpene levels can make smoke or vapor harsher.

Best for: choosing flavor, not for judging strength.

Tolerance and timing

Frequent use raises tolerance, which means the same 10 mg does less over time. Route of use and tolerance tend to matter more than body weight for most people. An empty stomach, alcohol, and some prescription medications can all change how a dose lands, so the same product can hit differently on a different day.

What to say at the counter

  1. What is the total THC in milligrams per serving or per gram?
  2. How many servings are in the package?
  3. What is the CBD to THC ratio?
  4. How fast does this format hit, and how long does it last?
  5. What is the lowest-dose version of this product you carry?

Buy the smallest dose that covers your goal, take it, then wait a full two hours before adding more if you chose an edible. Write down the product, the amount, and how you felt. Two or three notes will tell you more about your own potency range than any percentage on a shelf.