Free coffee brewing ratio calculator. Enter coffee weight, water amount and servings to find your brew ratio and per serving amounts.
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Divide water in millilitres by coffee in grams for the brew ratio, where 16 means 16 parts water to 1 part coffee. Divide water and coffee by servings for per serving amounts, which helps scale a recipe up or down without changing taste. One millilitre of water weighs one gram, so water weight and water volume are interchangeable here.
Ratio controls strength more than any other single variable. A 1 to 16 ratio, 20 g of coffee with 320 ml of water, suits many pour over brewers, while 1 to 15 tastes stronger and 1 to 17 tastes lighter. Keeping the ratio fixed while scaling servings preserves the flavour you liked, which is why weighing both coffee and water beats scoops and cups.
Pour over and drip coffee sit at 1 to 15 to 1 to 17, french press at 1 to 12 to 1 to 15, Aeropress at 1 to 10 to 1 to 16, Chemex at 1 to 15 to 1 to 17, moka pot at 1 to 7 to 1 to 12, cold brew concentrate at 1 to 8, and espresso at 1 to 2 of drink out per gram of coffee in. The SCA golden ratio of 55 g of coffee per litre, about 1 to 18, sits just lighter than most home brewing.
Enter coffee weight in grams, water in millilitres and the number of servings. Start at 1 to 16, taste the result, then move the ratio up or down by one step at a time until the brew suits you.
At 1 to 16, an 8 oz cup of 240 ml needs about 15 g of coffee, and a 12 oz mug of 355 ml needs about 22 g. Grams of coffee per cup are the reliable measure: a level tablespoon holds about 5 g, so one mug needs about 3 tablespoons, not 1 or 2.
Scaling a coffee recipe means multiplying both coffee and water by the same factor and keeping the ratio fixed. The seed example of 20 g and 320 ml for 2 servings gives 10 g and 160 ml per serving, and doubling it to 40 g and 640 ml for 4 servings tastes the same, provided grind stays similar.
Grind size and brew time work with ratio, not instead of it: french press uses coarse coffee for 4 minutes, pour over uses medium fine for 3 to 4 minutes, Aeropress uses fine for 1 to 2 minutes, Chemex uses medium coarse for 4 to 6 minutes, and moka pot uses fine for 5 to 8 minutes.
A stronger coffee ratio means a smaller second number: 1 to 15 is stronger than 1 to 17. If the cup tastes sour, grind finer first, since sourness usually means under extraction, while bitterness usually means over extraction. Change ratio for strength and grind for extraction.
A kitchen scale is the cheapest upgrade in coffee, because a scoop of dark roast holds less coffee than a scoop of light roast, and coarse coffee packs less densely than fine coffee. Weigh a level tablespoon of your own coffee once if you must use spoons, then use that weight every time.
A 1 to 16 ratio is a reliable starting point for pour over and drip brewing, with 1 to 15 for stronger coffee and 1 to 17 for lighter coffee. French press often uses 1 to 14 or 1 to 15.
The Specialty Coffee Association golden ratio is 55 g of coffee per litre of water, about 1 to 18. Most home brewers prefer slightly stronger, at 1 to 15 to 1 to 17.
For 12 cups, about 3 litres of drip coffee, use roughly 180 to 200 g of coffee at 1 to 15 to 1 to 17. Remember a coffee maker cup is only 5 to 6 oz, so a 12 cup maker holds about 1.8 to 2.1 litres, not 12 mugs.
About 15 g of coffee for an 8 oz, 240 ml cup at 1 to 16, and about 22 g for a 12 oz mug. For a standard 250 ml cup, 15 to 17 g suits most brewing methods.
About 3 level tablespoons per 8 oz mug, since one level tablespoon holds about 5 g. Two tablespoons per 6 oz cup is the common shorthand, close to 1 to 18.
French press needs coarse, pour over needs medium fine, Aeropress needs fine, Chemex needs medium coarse, and moka pot needs fine. Grind affects extraction: too fine tastes bitter, too coarse tastes sour.
French press takes 4 minutes, pour over 3 to 4 minutes, Aeropress 1 to 2 minutes, Chemex 4 to 6 minutes, and moka pot 5 to 8 minutes. Longer brewing extracts more flavour but can turn bitter if overdone.
Yes, the maths is the same, but use a cold brew ratio of 1 to 8 to 1 to 10 for concentrate and steep for 12 to 24 hours. Dilute concentrate before drinking, since it is far stronger than filter coffee.
The espresso ratio is explained by what it measures: the drink that comes out, not the water that goes in. A classic double uses 18 g of coffee to 36 g of espresso, written 1 to 2, in 25 to 30 seconds.