AeroPress Go measurements. What volume do AeroPress marks correspond to?

As a new owner of an AeroPress Go coffee brewer, I was surprised not to be able to find (either in the manufacturer’s manual or online) what the circle marks on the AeroPress chamber correspond to, or how much ground coffee fits into the included scoop. So here are my own measurements. They all assume the non-inverted brewing method with a single standard paper filter.

Chamber volume

For each of the three circle marks, I include three measurements: the bottom, the middle, and the top of the circle. I measured these both experimentally (pouring and weighing the water) and mathematically (based on the diameter of the chamber and the height of the marks).

These measurements are of the empty chamber. In reality, you will have some coffee grounds in it, so you have to account for their volume. (Here I assume that when you pour the water initially, it doesn’t mix much with the grounds, and so the combined volume should be approximately the sum of the coffee volume and the water volume. I didn’t attempt to verify this experimentally yet.)

The volume of the AeroPress Go scoop is 30 ml, so the last column in the table below contains the adjusted volume assuming you have 30 ml of grounds in the chamber. The numbers here are rounded to the nearest 5 ml.

Coffee grounds weight

As I mentioned above, the volume of the included scoop is 30 ml. In my measurements, I found 1 level scoop to contain around 13 g of ground coffee, more or less independent of the grind size (which was a bit surprising).

Another number for the density of ground coffee that I found online is 0.32 g/ml, resulting in 10 g per level scoop.

Brewed coffee yield

How much water should you pour to get X ml of brewed coffee? I found the output/input ratio to vary from 80% for a small portion to 90% for a large portion, assuming 1 scoop (13 g) of ground coffee and 2 minutes of brewing time.