Coffee Extraction Yield Calculator (TDS)
Share of the ground coffee that ended up dissolved in your cup, from the dose, the brewed weight and a refractometer TDS reading.
Results
Extraction yield
18.0
%
Brew ratio (beverage ÷ dose)
2.00
:1
Coffee solids dissolved
3.24
g
Compared with the usual 18–22 % target
Within the usual target
What this tool does
Strength (TDS) and extraction are different things: strength is how concentrated the cup is, extraction is how much of the coffee you dissolved to get there. The same 9 % TDS espresso can be under- or over-extracted depending on the dose and the yield. A target of roughly 18–22 % extraction is widely used as a starting point for balanced flavour, but taste rules — light roasts often taste best extracted higher. Weigh the beverage rather than measuring volume, because crema and foam make volumes misleading.
Formula
extraction yield = TDS × beverage mass ÷ dose
Variables
| Symbol | Meaning | Unit |
|---|---|---|
ds | Dry coffee dose | g |
bv | Brewed coffee in the cup | g |
tds | TDS (refractometer reading) | % |
EY | Extraction yield | % |
BR | Brew ratio (beverage ÷ dose) | :1 |
DC | Coffee solids dissolved | g |
VD | Compared with the usual 18–22 % target | — |
Worked example
- Dry coffee dose18 g
- Brewed coffee in the cup36 g
- TDS (refractometer reading)9 %
- Extraction yield18.0 %
- Brew ratio (beverage ÷ dose)2.00 :1
- Coffee solids dissolved3.24 g
- Compared with the usual 18–22 % targetWithin the usual target
Limitations
- The result is an estimate based only on the values you type. Real situations often include factors this calculator does not know about.
- The default values are typical reference figures, not measurements of your situation. Replace them with your own data whenever you have it.