Coffee Ratio Calculator ☕

Using the coffee ratio calculator

Work through the form from the top.

1. Pick the brewing method. Each method has its own typical ratio. Choose Custom ratio to type your own number of water parts, for example 17 for 1:17.
2. Choose how strong you want the coffee: mild, average, strong or robust. The espresso and Golden Cup settings use a fixed ratio, so this choice does not change them.
3. Fill in how much coffee to make (cups, mugs, fluid ounces, legal cups or milliliters) or the amount of ground coffee you plan to use (grams, ounces, spoons or milliliters). Use one of the two. If both are filled in, the amount of coffee to make is used.

With the amount to make filled in, you get the ground coffee and water needed. With ground coffee filled in, you get the water to pour and roughly how many cups that makes. With both empty, you see the ratio and the weights for a single cup.

In this calculator a coffee cup is 8 fl oz (236 ml) and a coffee mug is 350 ml. Volumes of water are converted to grams with a small density adjustment, so the weights you see are close to, but not exactly, the volume in milliliters. Where the amount is given in milliliters, 1 ml is treated as 1 g of water. For other volume conversions see the milliliters to cups converter.

Coffee-to-water ratios by method

A brew ratio compares the weight of ground coffee with the weight of water. A ratio of 1:16 means 1 g of coffee for every 16 g of water. A smaller second number means more coffee and a stronger, heavier cup; a larger one means a lighter cup.

Espresso is fixed at 1:2 (Normale), 1:1.5 (Ristretto) and 1:3 (Lungo). The Golden Cup Standard uses 1:18.18.

These are starting points. Beans, roast level, water quality and personal taste all move the best number, so treat the first brew as a draft and adjust one thing at a time.

How to use a brew ratio by hand

Convert everything to weights first, then divide the weight of the water by the second number of the ratio.

coffee = water ÷ ratio

Example. You want to brew 600 g of water through a pour over at 1:16. The coffee is 600 ÷ 16 = 37.5 g. For a 1:17 mild cup you would use 600 ÷ 17 = 35.3 g, and for a 1:15 strong cup 600 ÷ 15 = 40 g.

Going the other way, if you have 30 g of coffee and a 1:15 recipe, the water is 30 × 15 = 450 g. The same arithmetic works in ounces, as long as both amounts use the same unit.

Ratios written as 3:50. Some guides write ratios in other forms. Divide the water by the coffee to get the familiar form: 50 ÷ 3 = 16.67, so 3:50 is the same as 1:16.67, which is 60 g of coffee per liter of water.

Notes on the main methods

French press. Immersion brewing extracts a little less efficiently than a pour over, so the ratio is somewhat richer: 1:15 for average strength, with 1:17 for a mild cup and 1:12 for a very bold one. For a one-liter press, that is about 66.7 g of coffee at 1:15, 58.8 g at 1:17 and 83.3 g at 1:12. The Aeropress is also an immersion method and uses nearly the same numbers.

Pour over (V60). The slower, filtered extraction suits lighter ratios. This is the method the Golden Cup guidelines were written around, so 1:16 to 1:18 is typical, and tightening to 1:15 gives a stronger cup. A pour over is also easy to adjust by changing grind size and pouring speed.

Cold brew. Steeping for 12 to 18 hours with cold water extracts slowly, so the grounds-to-water ratio is far richer. At 1:8, a liter of water takes 125 g of coffee, and the result is a concentrate that is usually diluted with water or milk before drinking. Mild cold brew sits near 1:10 and an intense concentrate reaches 1:5 or even 1:4.

The Golden Cup ratio

The Specialty Coffee Association's Golden Cup Standard describes a brew of about 55 g of coffee per liter of water, which is a ratio of 1:18.18 (1,000 ÷ 55). For 500 g of water that is 27.5 g of coffee. An older rule of thumb used about 1:16.67 (60 g per liter), and many people simply prefer a stronger number such as 1:15 or 1:16. The standard is a reference point for a balanced extraction, not a rule that every cup has to follow.

In practice, start from the standard if you want a clean, light cup and move towards 1:15 when you want more body.

Brewing a better cup

• Weigh your coffee and water. Scoops and spoons vary with roast, grind and how they are filled, and the spoon options in this calculator are only approximations, since ground coffee is much lighter than water per spoonful. A kitchen scale makes recipes repeatable, the same idea that baker's percentages bring to bread.
• Grind to suit the method, using the table below, and adjust finer or coarser if the cup tastes sour (grind finer) or bitter (grind coarser).
• Use hot, not boiling, water for most hot methods, roughly 90 to 96 °C (195 to 205 °F).
• Use fresh beans and grind just before brewing.
• Keep the gear clean. Old oils make coffee taste stale.

Espresso ratios explained

Espresso recipes are written as the dose of ground coffee compared with the weight of liquid espresso in the cup. A normale shot at 1:2 turns an 18 g dose into 36 g of espresso. A ristretto is shorter and thicker, at about 1:1.5 (27 g from an 18 g dose), and a lungo is longer, at about 1:3 (54 g from 18 g). The calculator uses the same ratio for the water it reports, which is a convenient planning figure but not a precise measure of what flows into the cup, since the grounds hold on to some of the water.

Pressure, grind and shot time interact, so use these ratios as a target while you tune the grind.