Coffee Brew Ratio Calculator
Work out the exact coffee-to-water ratio for any brew method — grams of coffee, water in ml or cups, and what ends up in the cup.
Classic pour-over strength. 1:16 means 1 gram of coffee for every 16 grams of water.
Enter an amount — the recipe updates as you type.
- Coffee
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- Coffee in tablespoons
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- Water
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- Water in other units
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- Brewed coffee in the cup
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- Ratio used
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Everything is worked out in your browser with plain arithmetic — nothing is uploaded, there are no ads and no sign-up. Ratios are by weight, so a kitchen scale beats a scoop every time.
How it works
A brew ratio is simply the weight of dry coffee against the weight of brew water, written
1:X. The calculator does one division: coffee = water ÷ X when you
know your water, or water = coffee × X when you know your dose. At 1:16, 500 g of
water needs 500 ÷ 16 = 31.3 g of coffee. The Specialty Coffee Association's Golden Cup
standard is quoted as 55 g of coffee per litre of water, which is the same as a ratio of
1:18.2 — the drip preset here uses the widely brewed 1:16.7 (60 g/L) mid-point, and you can
dial the slider to anything from 1:1.5 to 1:25.
Water is treated as 1 g = 1 ml, and the other units use the US customary definitions: 1 fl oz = 29.5735 ml, 1 cup = 8 fl oz = 236.6 ml, 1 mug = 12 fl oz. Tablespoons assume a level tablespoon of medium-ground coffee at about 5.3 g — a rough guide only, because grind size and bean density change it. The "in the cup" figure subtracts the water the spent grounds keep, estimated at 2 g of water per gram of coffee, which is why a 500 g brew pours out around 438 ml. Espresso is different: there the ratio is dose to liquid out of the basket, so no absorption is subtracted.
Frequently asked questions
What is the golden ratio for coffee?
The Specialty Coffee Association's Golden Cup standard is 55 grams of coffee per litre of water, which is the same as a brew ratio of about 1:18.2 by weight. In everyday brewing most people land a little stronger: 1:16 is the default for pour-over, 1:15 for a French press and roughly 1:16.7 (60 g per litre) for a filter machine. Ratios are always by weight, so 1:16 means 1 gram of dry coffee for every 16 grams of water — at 500 g of water that is 500 ÷ 16 = 31.3 g of coffee.
How many grams of coffee do I need per cup of water?
A US cup is 8 fl oz, or about 237 ml of water, which needs roughly 14.8 g of coffee at 1:16 — close to 3 level tablespoons, since a level tablespoon of medium-ground coffee is about 5.3 g. Be careful with the word "cup": a drip coffee maker's marked cup is only 5 fl oz (about 148 ml), so a "12-cup" carafe holds about 1.8 litres and takes around 110 g of coffee. Weighing on a scale is far more reliable than scooping, because grind size and bean density change how much fits in a spoon.
Why is there less coffee in the cup than water I poured in?
The spent grounds keep some of it. A widely used estimate is that ground coffee retains about 2 grams of water per gram of dry coffee, so a 500 g brew at 1:16 uses 31.3 g of coffee, holds back roughly 63 g of water in the bed and pours out around 438 ml. This calculator shows that figure so you can scale a brew to fill a specific carafe. Espresso is the exception: there the ratio describes dose in to liquid espresso out — 18 g in and 36 g out — so nothing is subtracted.