With water accounting for more than 98% of brewed coffee, it is important to ensure good water quality when transforming roasted coffee into a beverage. For an optimal brew, use odorless and colorless filtered water or good-quality spring water. Avoid the use of distilled water, as it will extract the coffee much too aggressively.

Ideally, water for coffee making should have a neutral pH (7.0) and a total dissolved solids (TDS) count of roughly 120 ppm.