Tinctures vs Powder

Does anyone know how to calculate the same dose between tinctures and powders?
I use 20 drops of Woodland Essence Sida Acuta. I want to try Samsara Sida Acuta 20:1 concentrated extract. I'm not sure how much powder 20 drops is. Anyone know how to calculate this?

No ideas about the 20:1 Concentrated extract.

But Sida Acuta at 1:5 (60% alcohol) tincture can be used 20-40 drops up to 4x daily.
Powder at 1-3 tablespoons in water (Hot water extraction is best).
-> Source: Herbal Antibiotics by Stephen Buhner

I would say as a very rough 'guesstimate', 20 drops equivalent would be anywhere from 1-2 Teaspoons in powder (3 teaspoons make a 1 tablespoon).

Either way, just start small and see how you react.