Find the right amount of coffee for your water, based on how strong you like it.
Brewing ratio is expressed as grams of coffee per gram (or milliliter) of water, written as "1:X". A ratio of 1:15 means 1 gram of coffee is used per 15 grams of water:
A lower ratio number (e.g. 1:13) gives stronger coffee because more coffee is used per amount of water, while a higher ratio number (e.g. 1:17) gives milder coffee. Lighter roasts can often handle and are preferred with a stronger ratio than darker roasts, since they tend to have a milder, more acidic flavor profile that comes through better with more coffee.
For filter coffee, a ratio between 1:15 and 1:17 is common, while stronger brewing methods like a French press often use around 1:12 to 1:15. Espresso uses an entirely different, much stronger ratio.
Different brewing methods extract flavor compounds from the coffee beans in different ways and with different brew times, so what tastes balanced with one method can taste thin or too strong with another.
The calculator treats a cup as 2 deciliters (200 ml), a common standard for coffee cups. This figure is for reference only and doesn't affect the actual coffee amount calculated.