What does the mg on a mushroom capsule label mean?

The short answer

The milligrams on a mushroom capsule label can count three different things: the weight of mushroom powder in the capsule, the weight of one measured compound such as psilocybin, or a calculated total that folds psilocybin and psilocin into one figure. Regulated labels say which: Oregon's labels list psilocybin and psilocin separately in milligrams, and Colorado's give "Total Psilocin" in milligrams.^{1, 2}

That question applies to every capsule product, including the microdose capsules sold by My Mushroom Dispensary, the shop for adults 21+ run by the team that publishes this site. Ask which compound the milligrams refer to, and ask for the lab report for that batch.

Milligrams of what? The numbers a label can carry

Labs, regulators and researchers use several conventions for "how much psilocybin", and the product weight isn't a potency figure at all.

The 0.719 is psilocin's molar mass divided by psilocybin's (204.27 and 284.25 in PubChem), and 1.4 runs the conversion the other way.⁸ Our page on psilocybin vs psilocin explains why. Here's one invented lab result read four ways. Its numbers are in arbitrary units, picked to keep the arithmetic easy: they don't describe any real mushroom or product, and none of the results is an amount to take.

One sample, four totals from 81.9 to 114, and the only thing that changed is the convention. That's why a milligram figure can't be compared with another until you know which convention each one uses.

A powder weight says how much mushroom is in the capsule, not how much psilocybin, and that share varies: across 14 P. cubensis strains grown under the same conditions, psilocybin ran from about 0.2% to 2.0% of dry weight.⁷ The strain potency guide covers that study. This site doesn't convert label figures into amounts to take.

What do regulated labels in Oregon, Colorado and New Mexico show?

In Oregon, the product information document that goes with each product must include its potency test results, so the numbers behind the label travel with it.¹ Oregon has also proposed switching its lab-report formula from total potential psilocin to total psilocybin equivalent; comments closed October 21, 2026.⁵ We covered the proposed formula change when it was filed.

These labels exist only inside state-regulated programs, where psilocybin is given in supervised, licensed settings. Psilocybin remains a Schedule I controlled substance under federal law,¹¹ and ordering it online or by mail is illegal under federal law and in every state.

What does a batch lab report (COA) show?

A certificate of analysis (COA) is the testing lab's report on a sample from one batch. Oregon potency reports give psilocybin and psilocin in mg per gram plus total potential psilocin, from samples taken by staff of an ORELAP-accredited lab.^{4, 1} Colorado's labs must be accredited to ISO/IEC 17025:2017 and test for psilocybin, psilocin, baeocystin, aeruginascin and norbaeocystin.²

A report describes a sample, not every capsule: Oregon's health authority says "potency testing results only reflect the specific sample tested at that point in time".¹²

Questions to ask of a lab report

• Which lab? A name and an accreditation you can look up.
• Which batch? A batch or lot number that matches the package.
• When? Sampling and test dates. Colorado requires retesting every nine months, and Oregon compliance tests expire after one year.^{2, 1}
• Which compounds? Psilocybin and psilocin, each listed on its own.
• Which method? Methods can disagree at low levels: a 2025 comparison found a 3.7-fold gap between two methods on one low-psilocybin sample, and the same team found that water during extraction let the mushroom's own enzymes turn psilocybin into psilocin.¹³
• Which units? mg per gram, percent by weight or mg per capsule. 1% by weight equals ten milligrams per gram, so a mix-up moves a number tenfold.
• Which basis? Dry weight or as received. Oregon tells labs not to adjust for moisture; New Mexico's proposal caps water content below 10%.^{4, 10}
• Which formula for any total? See the table above.

Why are homogenized products tested differently?

Single mushrooms differ, even within one strain: in the 14-strain study, psilocybin between mushrooms of the same strain varied with coefficients of variation of 12.81% to 23.39%.⁷ Homogenizing grinds many mushrooms into one uniform powder before sampling, and in a five-strain study a second lab got more precise results when several mushrooms were homogenized together.³

• Oregon has labs homogenize a composite of whole mushrooms before testing. Homogenized products fail if primary and duplicate samples differ by more than 20%.^{4, 1}
• Colorado treats a manufactured lot as evenly mixed only if each tested serving is within 15.0% of the labeled value.²
• New Mexico's proposal would require homogenization before sale, with capsules among the allowed forms.⁶

Homogenizing makes the label fit the batch more closely. It doesn't make the batch any stronger or weaker.

Red flags on a label or lab report

• No batch number, or one that doesn't match the package.
• No lab name, accreditation or date.
• A bare "mg" with no compound named, or a total with no formula.
• Impossible numbers. No compound can be more than 100% of a sample. For scale, the highest strain average for psilocybin in the 14-strain study was 1.96% of dry weight.⁷ Even journals slip: a 2025 abstract reported 9.9% to 19.3% psilocybin, about ten times other published values, possibly a unit error.¹⁴
• Compounds that shouldn't be there. Colorado fails any product containing 4-AcO-DMT or another synthetic tryptamine.² Of 8 mushroom gummies from Portland, Oregon smoke and vape shops, 6 contained 4-AcO-DMT and one labeled psilocybin-free contained psilocybin.¹⁵

A clean report describes a batch, not how you'll respond. Medicines matter too: see the interaction reference, and the glossary for terms on a report.