Calculators

Brew Ratio Calculator

Water for this brew

240 g

15 g coffee

This is a weight ratio. For water, 1 g is about 1 ml. Use the result as a starting recipe and adjust it based on how the coffee tastes.

Enter a coffee dose or water weight to calculate the matching amount. The default is 15 g coffee at 1:16, which is 240 g water. Treat that as a starting point, not proof that the cup will taste good.

Updated: Sep 1, 2026 Reviewed by: Content and layout review

What this calculator does

Brew ratio is the weight of coffee relative to the weight of water. A ratio of 1:16 means one part coffee and sixteen parts water. Fifteen grams of coffee with 240 grams of water is 1:16.

For home brewing, treat 1 gram of water as about 1 milliliter. The calculator converts coffee and water quantities by weight; it does not calculate extraction yield. Grind size, brew time, and water temperature still affect the result.

How to use it

If you already know the coffee dose, keep “I have coffee” selected. Change the dose or the ratio and the water updates. If you already know how much brewing water you will use, switch to “I have water” and the dose is derived. The 1:15, 1:16, and 1:17 buttons are common pour-over starting points. Golden Cup matches the old filter recommendation of 55 grams of coffee per liter of water, about 1:18.2.

Pour-over often starts here, then you adjust grind size if the brew runs too fast or too slow. Avoid changing ratio and grind at the same time, or you will not know which adjustment changed the flavor.

Where common ratios sit

Filter coffee has no single recipe. The SCAA Golden Cup standard described 55 grams of coffee per liter of water, plus or minus 10 percent, which lands around 1:16.5 to 1:20. Many brew guides still cite 1:16 as a working example. More coffee relative to water usually makes a stronger cup; more water usually makes a lighter one. A 2021 filter study also found that black-coffee drinkers liked a wide range of brew strengths.

Espresso uses a different dose-to-yield relationship. The 1:16 ratio is not intended for espresso.

What the number cannot tell you

The calculator does not replace a scale, and it does not replace tasting the cup. Spoons and scoops measure volume, not weight. Darker roasted beans are lighter, so the same spoonful may contain less coffee by weight. If the cup is too bitter or too thin, go back to the brew ratio page to separate strength from extraction, then decide whether to adjust the grind.

Common Misconceptions

  • Do I have to brew at 1:16?

    No. 1:16 is a common starting point. The SCAA Golden Cup filter recommendation is 55 g coffee per liter of water, plus or minus 10%. Espresso uses a different ratio; see the espresso page.

  • Should I measure water in milliliters or grams?

    This calculator uses grams. At home, 1 g of water is about 1 ml, so 240 g of water can be treated as 240 ml.

  • Is brew ratio the same as strength?

    No. Brew ratio is how much coffee and water you start with. Strength is how concentrated the drink is. See the brew ratio knowledge page.

  • Can I measure with a spoon?

    A spoon measures volume. Darker roasts are lighter, so a spoonful often holds less coffee. A scale is more stable for a weight ratio.

  • Will this number make the cup taste good?

    Not by itself. Grind, time, and water temperature still change extraction. Change one variable at a time.

Sources and Notes