Interactive Tool

Mushroom Dosage Calculator

Estimate a starting range in dried grams from your experience level and intended effect. Every result is an estimate, not a measurement — always start below the range shown.

What this calculator can and cannot tell you

PsyBear's free dosage calculator gives you a starting range in grams of dried Psilocybe cubensis, based on body weight, experience level, and intended effect. The result is an estimate, not a measurement. No online calculator can determine the psilocybin content of a specific mushroom, because potency varies by species, strain, growing conditions, drying, and storage. Start below the range shown and wait for full effects before considering more.

A mushroom dosage calculator estimates a starting range from incomplete potency information. It cannot measure the psilocybin content of an individual mushroom.

PsyBear editorial position

150lbs

Recommended Dose Range

0.5g – 1g

Low to Moderate Dose

Mild to moderate effects. Expect enhanced colors, mood lift, and creative thinking while remaining functional.

Stay in a comfortable environment. Have a trusted friend nearby.

Important Notes About Dosing

Species and Strain Potency Vary

Potency differs between species and between strains of the same species. Penis Envy varieties are widely reported to be stronger than Golden Teacher, but published per-strain potency data is limited — treat any specific multiplier with caution and start low with unfamiliar material.

Individual Sensitivity

Everyone responds differently. Some people are naturally more sensitive. Always start lower than recommended and increase gradually over multiple sessions.

Set and Setting Matter

Your environment and mental state significantly affect your experience. The same dose can feel very different in different contexts.

Empty Stomach

Taking mushrooms on an empty stomach (4-6 hour fast) typically results in faster onset and stronger effects. Eating beforehand can reduce intensity.

How this calculator works

Last updated · Methodology: PsyBear editorial (literature review)

What the result means
A range in grams of dried mushroom material, assuming Psilocybe cubensis. It is a starting point for planning, not a prescription.
Inputs used
Body weight, self-reported experience level, and intended effect. Nothing else is modelled.
Dose categories
Microdose 0.1–0.25 g. Low to moderate 0.5–2.0 g. Standard to deep 1.5–3.5 g, capped at 5.0 g. These bands are PsyBear's editorial definitions, matched to our dosage guides — they are not a clinical standard.
Body-weight adjustment
Non-microdose results are scaled by up to ±20% around a 150 lb (68 kg) reference. We include this as a coarse adjustment only: the evidence that body weight predicts psilocybin response is limited, and this is not a validated pharmacokinetic model.
Fresh versus dried
Every figure assumes dried material. Fresh mushrooms are mostly water, so the same material weighs substantially more fresh than dried and the two are never interchangeable. We do not publish a single fixed conversion ratio, because drying method and residual moisture change the result.
Not modelled
Species other than P. cubensis, individual strain potency, tolerance from recent use, preparation method, medications, and existing health conditions.

For documented potency by genus see our species guide, and for strain-level notes see the strain library.

Disclaimer
This calculator is for informational purposes only and does not constitute medical or legal advice. Psilocybin remains a Schedule I controlled substance under federal law in the United States and is illegal in many jurisdictions worldwide. Individual response to psilocybin varies significantly based on body chemistry, mental state, strain potency, and environmental factors. The recommendations provided are general guidelines only. Always start with a dose lower than recommended, use in a safe environment with trusted people, and never combine with alcohol, MAOIs, or other substances. If you have a personal or family history of psychosis, schizophrenia, or severe mental health conditions, do not use psilocybin. Consult a healthcare provider before use if you take any medications.
Common questions

Mushroom dosage calculator FAQ

Where can I find an accurate mushroom dosage calculator online?

PsyBear publishes a free dosage calculator that states its assumptions openly: the dose bands it uses, the species it assumes, and the inputs it ignores. No calculator anywhere can be accurate for a specific mushroom, because none of them can measure what you are holding. Judge any calculator by whether it shows its methodology and its uncertainty, not by how precise its number looks.

Can any online calculator give an exact psilocybin dose?

No. A calculator works from species-level averages and the inputs you type in; it has no information about the batch in front of you. Two mushrooms of the same strain, grown in the same flush, can differ in alkaloid content. Treat every calculator output — including PsyBear's — as a range to start below, not a measured dose.

Does the mushroom species change the dose?

Yes, substantially. Psilocybe cubensis, P. semilanceata and P. cyanescens are not interchangeable by weight, and published potency figures for them differ. PsyBear's calculator assumes dried P. cubensis, so if you are working with anything else the output does not apply. Our species guide covers what is documented for each genus.

Does fresh or dried weight matter?

It matters more than almost any other variable. Fresh mushrooms are mostly water, so the same material weighs substantially more fresh than dried. PsyBear's calculator assumes dried weight throughout. We do not publish a single fixed conversion ratio, because drying method and residual moisture change the result.

Does body weight actually affect psilocybin dosage?

Less than most calculators imply. PsyBear's tool applies a modest adjustment of up to ±20% around a 150 lb reference, and we flag it as a coarse adjustment rather than a validated model, because the evidence that body weight predicts psilocybin response is limited. Experience, setting, tolerance and the potency of the specific material all matter more.

What should I check before using a mushroom dosage calculator?

Whether you can identify the mushroom with certainty, since no calculator can confirm a species or detect adulteration. Whether you have a psychiatric history or take medications — lithium in particular is associated with serious adverse events. Whether psilocybin is legal where you are. And whether you have a sober person present, a cleared schedule, and a plan for getting help if you need it.