Coffee to Water Ratio Calculator

About this calculator

Coffee brewing strength is controlled by the ratio of coffee grounds to water by weight, commonly written as 1:15 to 1:18 for drip coffee or roughly 1:2 for espresso. Given a target water amount and a chosen ratio, the needed coffee is simply water ÷ ratio — for example, 500g of water at a 1:16 ratio calls for 500 ÷ 16 ≈ 31g of coffee.

Home baristas and coffee professionals rely on this ratio-based approach — rather than fixed scoop measurements — because it scales precisely to any batch size and produces a consistent, repeatable brew strength across different pot or cup sizes. Specialty coffee guides and roasters typically recommend a specific ratio range depending on the brew method, and this calculator lets someone dial in the exact gram amount for their equipment.