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How much water do you pour for 20 grams of coffee?
Published by Ratio Kettle
For 20 grams of ground coffee at a 1:16 ratio, pour 320 grams of water in total. If your recipe uses 1:15, pour 300 grams. At 1:17, pour 340 grams. These are input weights for filter brewing.
Write the last number first
Set your carafe and dripper on a scale. Rinse the filter if the recipe calls for it, empty the carafe, add the grounds and tare. The scale now tracks every gram of water added to the system, including the first pour that wets the grounds. Leave the whole assembly on the scale as water moves into the carafe.
Staying with the 320-gram example, try writing three cumulative scale readings on a recipe card: 60, 190 and 320 grams. That represents pours of 60, 130 and 130 grams. Begin each pour when the recipe or the height of the water bed calls for it. Keep the water below the rim.
Work backward when you have limited water
If the kettle holds 360 grams of usable brew water and you want the same 1:16 ratio, divide 360 by 16 to get 22.5 grams of coffee. Put rinse water aside before weighing the 360 grams. If your scale reads whole grams, 22 grams of coffee pairs with 352 grams of brew water.
Leave room for a taste adjustment
A ratio is one part of a recipe. Use the same beans, grinder setting and brewer when comparing two cups. To compare 1:16 with 1:15 at a fixed 20-gram dose, change the final pour target from 320 to 300 grams and write down what you taste after the coffee cools. If a bigger batch drains unevenly or overfills the brewer, switch to smaller batches or a larger brewer.