Coffee Brew Ratio Calculator

Why ratios beat recipes

A "recipe" (two scoops for four cups) depends on the scoop, the cup, and the mood. A ratio (1:15) scales perfectly from one cup to a thermos and adapts to any bean. The professional brew-bar standard is grams and ratios — and a $15 scale delivers more consistent coffee than most equipment upgrades.

The method bands

Espresso concentrates at 1:1.5–1:3; AeroPress is flexible (1:8–1:14 by recipe school); pour-over and drip live at 1:15–1:17; immersion methods (press) at 1:12–1:15. The bands are community-consensus, refined over decades — starting mid-band and adjusting by taste is the entire technique.

The adjustment grammar

Sour = under-extracted: grind finer, brew hotter, or steep longer. Bitter/harsh = over-extracted: grind coarser, brew cooler, or end sooner. Weak = wrong ratio, not wrong grind. Speaking this grammar turns every bad cup into a one-variable experiment — the difference between coffee people and people who drink coffee.