Coffee to Water Ratio
Coffee and water for a brew ratio from the cups you want, the water or the coffee, allowing for water the grounds keep, plus cold brew concentrate and dilution.
Grams of coffee and water at the ratio you choose, the brewed volume after the grounds’ retention and how many cups that is, grams per litre — and for cold brew the ready-to-drink volume and its effective ratio.
Example: Two 250 ml cups at 1:16 with grounds keeping 2 g per gram: 571 g water and 35.7 g coffee to fill the cups; 100 g at 1:5 diluted 1:1 gives 600 ml of cold brew.
One to sixteen,
give or take.
What a brew ratio is, why the cups mode brews more water than it serves, how cold brew concentrate is counted, and why the presets are only examples.
Ratio
A brew ratio is grams of water per gram of coffee: 1:16 is 62.5 g of coffee per litre. Given the water, coffee = water ÷ ratio; given the coffee, water = coffee × ratio. Ratios between 1:15 and 1:17 are common for filter coffee, 1:12 for a French press, 1:4 to 1:8 for cold brew concentrate — examples, not rules; the ratio you like is the input.
Retention
Spent grounds hold water — about twice their own weight, as commonly published — so the brew that comes out is less than the water that went in. Starting from cups, the page brews enough water that the cups are full after retention; enter 0 to ignore it.
Cold brew
Cold brew is made strong and diluted: brewed at the concentrate ratio, retention taken off, then water added in the parts you enter. The ready-to-drink volume and the effective ratio (all water over the coffee) are shown so a concentrate can be compared with a hot brew.
What the number does not settle
Grind, water temperature, time and the coffee itself decide the cup; the page settles only the weights. Inputs stay in your browser; the same anonymous usage counts as the rest of the site apply.