Coffee Extraction Yield Calculator

Calculate your extraction yield from TDS readings and check it against the SCA Golden Cup standard.

%
g
g
Extraction Yield
22.50%
Optimal
Brew Ratio
1:16.7
SCA Golden Cup
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Extraction Range (18% — 22% optimal)
0%10%18%22%30%50%
Adjustment Suggestions
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How to Use This Coffee Extraction Calculator

  1. Measure your TDS — use a coffee refractometer to read the Total Dissolved Solids percentage from your brewed coffee. If you do not have a refractometer, start with a typical value (1.15-1.35% for drip, 8-10% for espresso).
  2. Enter your beverage weight — weigh the final brewed coffee in grams (excluding grounds). For a single pour-over cup, this is typically 250-350g.
  3. Enter your coffee dose — the dry weight of ground coffee used, in grams.
  4. Select your brew method — this provides context-specific guidance for adjusting your technique.

Understanding Coffee Extraction

Coffee extraction is the process of dissolving soluble compounds from roasted coffee grounds into water. A roasted coffee bean contains roughly 28-30% soluble material by weight — the rest is insoluble cellulose fiber. However, not all of those solubles taste pleasant. The art of brewing is dissolving the right amount: enough to capture sweetness, acidity, and body, but not so much that you pull out the bitter, astringent, and ashy compounds that dissolve last.

The Extraction Yield Formula

Extraction yield quantifies what fraction of the dry coffee grounds actually dissolved into your brew:

EY = (TDS × Beverage Weight) / Coffee Dose

Where EY = extraction yield (%), TDS = total dissolved solids (%), Beverage Weight = mass of brewed coffee (g), and Coffee Dose = mass of dry grounds (g).

What TDS Tells You

TDS measures the strength (concentration) of your brew — how much dissolved coffee is in each sip. The SCA recommends 1.15-1.35% TDS for drip coffee. Espresso is much stronger at 7-12% TDS. TDS alone does not tell you if the coffee is well-extracted; you need to combine it with the brew ratio to calculate extraction yield.

The SCA Golden Cup Standard

The Specialty Coffee Association defines the Golden Cup standard as coffee brewed with an extraction yield of 18-22% and a TDS of 1.15-1.35%. These ranges were established through decades of sensory research showing that most people prefer coffee within these parameters. Below 18%, the brew tends to be sour and underdeveloped. Above 22%, it becomes bitter and astringent.

How Grind Size, Water Temperature, and Time Affect Extraction

Grind size is the most powerful variable. Finer grinds expose more surface area, increasing extraction rate. If your coffee is under-extracted, grind finer. If over-extracted, grind coarser. Water temperature accelerates extraction — the SCA recommends 92-96°C (197-205°F). Cold brew uses room temperature or cold water but compensates with 12-24 hours of steeping time. Brew time is the total contact time between water and grounds. Longer contact means more extraction. Pour-over takes 3-4 minutes, French press 4-5 minutes, and espresso just 25-30 seconds at high pressure.

Brew Method Differences

Espresso uses high pressure (9 bar) and a fine grind to achieve a concentrated brew in under 30 seconds. A typical shot is 18g dose yielding 36g of liquid at 8-10% TDS. Pour over uses gravity and a medium grind with a brew time of 3-4 minutes. French press is full immersion with a coarse grind, producing a heavier body due to the metal mesh filter allowing oils and fines through. AeroPress is versatile, supporting both immersion and pressure techniques. Cold brew extracts slowly at low temperatures, yielding a smooth, low-acid concentrate.

Frequently Asked Questions

Extraction yield is the percentage of the dry coffee grounds that dissolved into the water during brewing. A coffee bean is about 30% soluble, but not all solubles taste good. The optimal extraction range of 18-22% captures the desirable flavor compounds while leaving behind the harsh, bitter ones.
TDS (Total Dissolved Solids) is the concentration of dissolved coffee solubles in the brewed beverage, measured as a percentage. It is typically measured with a refractometer. For drip coffee, the SCA recommends a TDS of 1.15-1.35%. Espresso has a much higher TDS, typically 7-12%.
The Golden Cup standard, defined by the Specialty Coffee Association (SCA, formerly SCAA), specifies the ideal brewing parameters: a TDS of 1.15-1.35% with an extraction yield of 18-22%. Coffee brewed within these ranges is considered optimally balanced, with the best combination of sweetness, acidity, and body.
Below 18% extraction, the brew is under-extracted: the water has not dissolved enough of the desirable flavor compounds, resulting in sour, salty, or thin-tasting coffee. Above 22%, the brew is over-extracted: the water has dissolved too many of the bitter, astringent compounds that dissolve last, producing harsh, hollow, or ashy flavors.
TDS is measured with a coffee refractometer, such as the VST LAB Coffee III or Atago PAL-COFFEE. Place a few drops of brewed coffee on the lens, wait for the reading to stabilize, and record the TDS percentage. For accuracy, measure at a consistent temperature (around 20-25°C) and stir the brew before sampling.