About the Coffee Ratio Calculator
This coffee ratio calculator tells you how much ground coffee and water to use for your brew method. Choose pour-over, drip, French press, AeroPress, moka pot, espresso or cold brew, then tell it how many cups you want, how much water you have, or how much coffee is left in the bag. It returns the coffee in grams and approximate tablespoons, the water in millilitres and ounces, and the amount of drinkable coffee you will end up with.
Brew ratios are written as 1:X — one part coffee to X parts water by weight. The Specialty Coffee Association’s brewing standard of about 55 g of coffee per litre of water works out to roughly 1:18, most filter brewers work between 1:15 and 1:18, immersion methods like French press are usually a little stronger at about 1:15, and cold brew is made as a strong 1:5 concentrate or a ready-to-drink 1:8. For espresso the ratio compares dry coffee to liquid espresso in the cup, typically 1:2.
Because 1 ml of water weighs 1 g, you can use a scale for both. Start with the default ratio for your method, then adjust: fewer parts water makes it stronger, more makes it lighter. Grounds hold back roughly 2 ml of water per gram, so the brewed yield is a little less than the water you pour.
How to use the coffee ratio calculator
- 1Choose your brew method, or pick custom and set your own ratio.
- 2Decide whether to calculate from cups, water or the coffee you have.
- 3Enter the amount.
- 4Weigh out the coffee and water shown, and grind to the suggested size.
- 5Taste and adjust: a lower ratio number is stronger, a higher one is milder.
Formula and method
A brew ratio 1:R means one gram of coffee for every R grams of water. Since a millilitre of water weighs a gram, the calculator divides the water by R to get the coffee dose, or multiplies the coffee by R to get the water. When you choose cups, each cup is 8 US fluid ounces (236.6 ml) of water.
Spent grounds retain about 2 ml of water per gram, so the drinkable yield is the water minus twice the coffee weight. Tablespoon amounts assume about 5 g of ground coffee per level tablespoon, which varies with roast and grind — a scale is more accurate. For espresso the ratio is dose to beverage weight.
- R
- Parts water per part coffee (e.g. 16 for 1:16)
- C
- Ground coffee in grams
- W
- Water in grams (= millilitres)
Worked examples
Two cups of pour-over
Two 8 fl oz cups is 473 ml of water. At 1:16 that needs 29.6 g of coffee, about 6 tablespoons. Grounds hold back around 59 ml, leaving roughly 414 ml to drink.
French press with 1 litre of water
At 1:15, 1,000 ml of water needs 66.7 g of coarse-ground coffee — about 13 level tablespoons.
Cold brew concentrate from a 100 g bag
A 1:5 concentrate uses 500 ml of water for 100 g of coffee. The grounds soak up about 200 ml, leaving 300 ml of concentrate — around 600 ml of drinkable coffee once diluted 1:1.
Frequently asked questions
What is the best coffee to water ratio?+
For filter and pour-over coffee most brewers start at 1:16 (for example 30 g of coffee to 480 ml of water) and adjust between 1:15 and 1:18 to taste. French press is usually a touch stronger at around 1:15.
How many tablespoons of coffee per cup?+
For an 8 oz cup at 1:16 you need about 15 g of coffee, roughly 3 level tablespoons of ground coffee. The traditional “2 tablespoons per 6 oz” rule gives a similar strength.
What ratio should I use for cold brew?+
Use about 1:5 for a concentrate that you dilute 1:1 with water or milk, or 1:8 for cold brew ready to drink. Steep coarse grounds in the fridge for 12–24 hours and filter.
What is the ratio for espresso?+
A standard espresso is about 1:2 — for example 18 g of ground coffee producing 36 g of liquid espresso in 25–30 seconds. A ristretto is around 1:1–1:1.5 and a lungo 1:3 or more.
Why weigh coffee instead of using scoops?+
Coffee density changes with roast level and grind, so a tablespoon can hold 4–7 g. Weighing both coffee and water on a scale gives the same strength every time and makes ratios easy to follow.