Cold Brew Coffee Ratio Calculator

About this calculator

Cold brew coffee is made by steeping coarsely ground coffee in room-temperature or cold water for 12–24 hours rather than using heat and pressure, and the result is governed almost entirely by the coffee-to-water ratio — commonly 1:4 to 1:8 by weight for a concentrate meant to be diluted, or closer to 1:15 for ready-to-drink strength — since cold extraction pulls out flavor compounds far more slowly than hot brewing.

Because there's no heat to speed up extraction, ratio is the primary lever cold brew makers have to control strength and bitterness: a tighter ratio (more coffee per water) yields a concentrated syrup diluted later with water, milk, or ice, while a looser ratio produces a brew that's ready to drink straight from the fridge.

Home coffee enthusiasts dialing in their cold brew, coffee shops standardizing a house recipe, and coffee equipment guides all reference specific coffee-to-water ratios like this because, unlike hot brewing, temperature and time are less forgiving levers for cold extraction — ratio does most of the work.