Choose how you brew, then say how many cups you want, how much water you’re using, or how much coffee you have left. The brew ratio (coffee : water) is filled in for each method; change it to make your coffee stronger or milder.
Coffee is brewed by weight: grams of coffee to grams of water. Since 1 ml of water weighs 1 g, a 1 : 16 ratio means 1 g of coffee for every 16 ml of water. Two 250 ml cups is 500 ml of water, so 500 ÷ 16 = 31 g of coffee.
A lower second number makes stronger coffee: 1 : 15 is stronger than 1 : 17. Immersion methods like the French press often use a little more coffee than drip; espresso and moka pots use far more, and cold brew is often made as a strong concentrate and diluted with water or milk.
For espresso the ratio compares the dry dose to the liquid shot that comes out: 18 g of coffee in, 36 g of espresso out, at 1 : 2. For every other method it compares coffee to the water you pour in. The grounds soak up about twice their weight in water, so you’ll get a little less in the cup than you poured.
At the popular 1 : 16 ratio, a 250 ml (8.5 oz) mug needs about 16 g of coffee, roughly 3 level tablespoons. For a stronger cup use 1 : 15 (17 g); for milder, 1 : 17 (15 g).
The Specialty Coffee Association’s “golden cup” guideline is 55 g of coffee per litre of water, about 1 : 18. Most home brewers find 1 : 15 to 1 : 17 a tasty place to start.
Use about 1 : 15: for a 1-litre press, 67 g of coarse-ground coffee. For a 350 ml (3-cup) press, about 23 g.
For ready-to-drink cold brew use about 1 : 8 (125 g coffee per litre of water). For concentrate use 1 : 5 (200 g per litre), then dilute 1 : 1 with water or milk. Steep coarse grounds 12–24 hours in the fridge.
About 2 level tablespoons. A level tablespoon of medium-ground coffee weighs about 5 g, but it varies with grind and roast, so a scale is more reliable.
