A coffee-to-water ratio you can actually use

A brew ratio describes the relationship between the amount of dry coffee and water used. A starting range such as 1:15 to 1:17 means one gram of coffee for fifteen to seventeen grams of water. At 1:16, a 20-gram dose uses 320 grams of brewing water. That arithmetic makes it easier to scale a recipe than counting differently sized scoops.

The number alone does not explain the finished cup. Some water remains in the grounds, and an immersion brewer behaves differently from a method in which water flows through a coffee bed. Espresso recipes may instead express the relationship between dry coffee and the beverage produced, so always check which two quantities a recipe is comparing.

Use the ratio as a stable reference while evaluating grind, contact time and technique. If a drink is too concentrated, dilution may be a different solution from changing extraction. If you change both dose and grind at once, the result becomes harder to interpret. Record your chosen ratio, taste the coffee and adjust deliberately; a familiar starting range is a useful tool, not a universal definition of a good cup.