What is extraction yield?

Extraction yield is the percentage of coffee's soluble mass that dissolves into your cup. The ideal range is 18-22%. Below 18% tastes sour (under-extracted), above 22% tastes bitter (over-extracted).

How do I calculate extraction?

Extraction % = (Beverage Weight × TDS%) ÷ Coffee Dose × 100. You need a refractometer to measure TDS (Total Dissolved Solids).

What refractometer should I use?

Popular options include VST LAB Coffee III (~$700), Atago PAL-Coffee (~$300), and DiFluid R2 Extract (~$150).

Extraction Yield Calculator

EXT.CALC Refractometer Required

Coffee Dose Dry coffee weight

Beverage Weight Final liquid weight

TDS Reading Total Dissolved Solids %

Extraction Yield --%

Under

Ideal

Over

16% 18% 20% 22% 24%

Enter your values above to calculate extraction.

Brew Type:

The Formula

Extraction % = (Beverage Weight × TDS%) ÷ Dose × 100

This formula tells you what percentage of the coffee's soluble mass you dissolved into your cup. Most specialty coffee targets 18-22% extraction.

Ideal Ranges

Espresso 18-22%

Standard specialty espresso range. Light roasts often extract better at 20-22%.

Filter 18-22%

SCA Golden Cup standard. Some prefer 19-20% for balanced cups.

Cold Brew 12-18%

Lower extraction due to cold water. Concentrate may be higher.

Understanding Results

Under-extracted (<18%)

Sour, grassy, underdeveloped. Grind finer, increase time, or raise temperature.

Ideal (18-22%)

Balanced sweetness, acidity, and body. Where most specialty coffee tastes best.

Over-extracted (>22%)

Bitter, astringent, hollow. Grind coarser, decrease time, or lower temperature.

Equipment Needed

This calculator requires a refractometer to measure TDS. Popular options:

VST LAB Coffee III (~$700)
Atago PAL-Coffee (~$300)
DiFluid R2 Extract (~$150)

Without a refractometer, use taste and our Dial-In Assistant instead.

The Science of Extraction

Understanding what happens when water meets coffee.

Soluble Content

Coffee beans are ~30% soluble by mass. The rest is insoluble cellulose fiber. Our goal is to dissolve the right 18-22% of that 30%.

Extraction Order

Compounds extract in order: acids first (sour), sugars next (sweet), then bitter compounds. Under-extraction tastes sour; over-extraction tastes bitter.

TDS vs Extraction

TDS measures concentration (strength). Extraction measures how much you dissolved. You can have high TDS with low extraction (ristretto) or vice versa.

Roast Impact

Darker roasts are more soluble and extract faster. Light roasts resist extraction—they often need higher temps, finer grinds, or longer times.