Coffee Calculators

Ratios, extraction, dilution and caffeine. 12 calculators covering espresso, pour over, French press, AeroPress, moka and cold brew.

Brew ratio is the single most useful number in coffee and the one most recipes bury. Written as coffee to water by weight, 1:16 is a common filter starting point and 1:15 is a little stronger. Volume measures are the problem: a “scoop” of coffee varies by grind and by bean density enough to move the ratio by 20%, which is the difference between a good cup and a thin one. Weighing both sides makes a recipe repeatable between kitchens, and that is the entire reason scales became standard equipment.

Espresso extraction works in yield rather than time. A typical modern shot is 1:2, so 18 g in and 36 g out, and the time follows from the grind rather than being the target. People chasing “25 seconds” while ignoring output weight are holding the wrong variable fixed.

Cold brew pages handle concentrate separately from ready-to-drink, since a 1:5 concentrate diluted at serving and a 1:15 direct brew end up in similar places by very different routes.