5 min read · updated 2026-08-10
For dried Psilocybe cubensis: 1 to 1.75 g is a light dose, 1.75 to 2.5 g is a common dose, 2.5 to 5 g is strong, and 5 g and up is heavy. The 25 mg dose used in the depression trials works out at roughly 4 g of dried cubensis.
The tiers, and what they feel like
| Tier | Dried cubensis | What to expect |
|---|---|---|
| Microdose | 0.05–0.3 g | Nothing you can feel. If you can tell, it is not a microdose. |
| Threshold | 0.3–1 g | Mild body load, colours a little brighter, mood shift. Still functional. |
| Light | 1–1.75 g | Clear change. Surfaces breathe, emotions amplify. Not a working dose. |
| Common | 1.75–2.5 g | Full effect. Strong closed-eye visuals, altered thought, feelings in waves. |
| Strong | 2.5–5 g | Loss of ordinary self-reference, heavy visuals, time comes apart. |
| Heavy | 5 g+ | Overwhelming for most people, experienced included. |
Why species matters more than grams
Published dose tables are cubensis tables whether they say so or not. Some wild species are far stronger: Psilocybe azurescens is roughly three times cubensis, so a gram of it is like three grams of cubensis. Thinking in grams instead of in active content is exactly how people who have taken mushrooms many times get caught out by an unfamiliar species. The dose calculator scales the tiers by each species' measured potency so you can compare like for like.
Why there is no exact number
Alkaloid content varies up to fourfold between flushes of the same genetics. No calculator can turn a weight into a precise dose, because the material itself is not precise. That uncertainty is the single most important fact about dosing, and it points one way: with material you have not had before, go under what the table says and give it a full two hours before deciding anything. Most bad experiences that start with a dose start with a redose taken on top of one that had not finished coming up.
Common questions
How many grams of shrooms should a beginner take?
Somewhere in the 1 to 2 g range of dried cubensis for a first time, with a cleared day and ideally someone sober around. If the material is unfamiliar, start at the low end and wait two full hours before considering more.
Is 3.5 grams a lot?
An eighth (3.5 g) of dried cubensis is a strong dose. It is enough to lose ordinary self-reference and have heavy visuals, and it is not a beginner dose. The 25 mg used in clinical trials is about 4 g.
How much is a microdose?
0.05 to 0.3 g of dried cubensis, taken on a schedule with days off. It is meant to be sub-perceptual: if you feel it, you have taken too much for a microdose.
Keep reading
Sources
- [1]Stamets, Psilocybin Mushrooms of the World (1996)
- [2]Hasler et al., 'Acute psychological and physiological effects of psilocybin in healthy humans' (2004)