Coffee Extraction Yield Explained: TDS, Beverage Mass, Dose, and the Basic Math
Extraction yield estimates the percentage of the dry coffee dose that ends up dissolved in the brewed beverage. It is useful because it separates how much material was removed from the grounds from how concentrated the final drink tastes.
The basic extraction-yield formula
A common practical calculation is:
Extraction Yield % ≈ (Beverage Mass × TDS %) ÷ Dry Coffee Dose
Example: a filter brew produces 300 g of beverage at 1.35% TDS from an 18 g coffee dose.
(300 × 1.35) ÷ 18 = 22.5% extraction yield
The formula uses TDS as a percentage number. If software uses TDS as a decimal fraction, the calculation format will look different.
Strength vs. extraction yield
TDS measures beverage concentration. Extraction yield estimates how much of the original coffee mass became dissolved solids. A beverage can therefore be strong but comparatively low in extraction, or weak but relatively highly extracted.
For espresso, a short ristretto can have high TDS because it is concentrated even when total extraction is lower than a longer shot.
Why the calculation is an estimate
Real brewing is more complicated than the simple equation. Grounds retain water, some dissolved material remains trapped in the coffee bed, filters retain oils and particles, and espresso measurements are affected by very small beverage masses and high concentrations. Refractometer technique, sample cooling, crema handling, and instrument calibration also matter.
What numbers are useful?
Traditional brewing-control charts often reference extraction near the high teens to low twenties as a broad region where many coffees taste balanced, but a target number should never replace sensory evaluation. Light roasts, modern espresso styles, unusual processing, and different brew methods can taste excellent outside old reference ranges.
Use extraction yield for comparison
The most useful application is controlled experimentation. If two brews use the same coffee but one tastes hollow and measures substantially lower in extraction, the measurement helps confirm what the palate suggests. If a brew measures high but tastes dry and uneven, the problem may be channeling, fines migration, or excessive agitation rather than simply “too much extraction.”
A refractometer provides TDS measurements, while a precise scale supplies dose and beverage mass. For brewing equipment, browse brewing equipment.
For more terminology, visit the Coffee, Espresso & Brewing Equipment Glossary.
