Coffee Brewing Ratio Calculator
Calculate coffee grounds and water for any brew strength and yield. Supports pour-over, French press, AeroPress, and drip ratios.
What this calculates
Brewing good coffee comes down to the ratio of grounds to water (plus grind size, water temp, and time). The SCA standard is 1:16 to 1:18 by weight. This calculator works in either direction: enter the cup volume you want and get the grounds needed, or enter grounds and see the water for your preferred ratio.
Formula & how it works
Grounds (grams) = water (grams) ÷ ratio. Water and grounds measured by weight (1 mL water ≈ 1 g). Common ratios: 1:15 strong, 1:16 standard SCA, 1:17 mild, 1:18 weak. French press often uses 1:12-1:14 because the brew sits with grounds. Espresso is much tighter (1:2).
Worked example
Want 500 mL of pour-over at SCA standard 1:16. Grounds = 500 ÷ 16 = 31.25 g. Round to 31 g. Use that with 500 g water at 96 °C, ground medium-fine, with a 3-4 minute total brew time.
Frequently asked questions
Why measure by weight not volume?
Coffee beans vary in density (lighter roasts are denser; darker roasts puff up). A 'tablespoon of coffee' is wildly variable. Grams are consistent and the difference between a great and mediocre brew.
What grind size for pour-over?
Medium to medium-fine — like coarse sand. Too fine = bitter/sour over-extraction. Too coarse = weak/sour under-extraction. Burr grinder is essential; blade grinders produce too much variation.
Does water matter?
Significantly. Aim for 95-96 °C (203-205 °F) just off boil. Soft water with some minerals brews better than distilled (no taste vehicles) or hard (mineral aftertaste). SCA water standards exist.
What's the 1:2 espresso ratio?
Brew ratio for espresso: 18 g grounds → 36 g espresso in cup (1:2). Time around 25-30 seconds. Much more concentrated than filter coffee — different process, different beans encouraged.