Coffee-to-Water Ratio Calculator

Dialing in the ratio of coffee to water is the single biggest lever you have over how a cup tastes, and it carries across every brewer on the counter. Getting that balance right is what separates a brew worth the beans from one that ends up down the drain. The aim is to hit the band where extraction is full but not bitter, consistently, batch after batch.

The math runs on weight, not volume. You pick a method and the number of cups, and the tool applies a fixed coffee-to-water ratio by weight: 1:16 for drip, 1:15 for pour-over, 1:14 for French press, 1:5 for cold brew and 1:2 for espresso. A cup is counted as 237 ml of water (30 ml per espresso shot). Light strength stretches the ratio by 10% and Strong tightens it by 15%; coffee grams = water ÷ ratio, also shown in tablespoons at 5 grams each.

A kitchen scale is non-negotiable here, since scooping by volume gives wildly inconsistent doses. Immersion methods like French press and cold brew lose a real fraction of their water to the grounds, and the calculator doesn't correct for that, so you'll pour out a little less coffee than the water you add. One trap worth flagging: not every method wants boiling water. For pour-over, the National Coffee Association recommends water at 93 ± 3°C (roughly 194-205°F), while cold brew uses no hot water at all.