What is the best coffee to water ratio?

The Specialty Coffee Association (SCA) recommends a golden ratio of approximately 1:18 (about 55 grams of coffee per litre of water). Most specialty coffee drinkers use ratios between 1:15 (strong) and 1:18 (light). The ideal ratio depends on your brew method and personal taste: espresso uses 1:2, French press typically uses 1:15, pour over 1:16 to 1:17, and cold brew 1:8.

How many grams of coffee do I need for 250 mL of water?

At a 1:16 ratio, 250 mL of water requires 250 / 16 = 15.6 grams of coffee. At 1:15 (stronger) you need 16.7 grams, and at 1:17 (lighter) you need 14.7 grams. Since water weighs 1 gram per millilitre, 250 mL of water weighs 250 grams. Simply divide the water weight in grams by your chosen ratio to get the coffee dose.

How do I measure coffee to water ratio without a scale?

A digital kitchen scale is strongly recommended for accurate coffee ratios. Without one, a rough guide is: 1 tablespoon of ground coffee weighs approximately 5 to 7 grams (depending on grind size and coffee density). For a standard 250 mL cup at 1:16, you would need about 2 to 3 tablespoons. Volume measurements are much less accurate than weight, so using grams gives more consistent results.

Coffee to Water Ratio Calculator

Work out the exact water amount for your coffee dose, or how much coffee you need for any volume of water. Enter your coffee weight in grams, choose a ratio preset for your brew method, or set a custom ratio.

Water weighs 1 gram per millilitre at room temperature, so millilitres and grams are interchangeable for water in these calculations.

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Standard Method Based on Specialty Coffee Association (SCA) brewing standards.

1. Your Coffee

What do you want to calculate?

Coffee dose (grams)

Water volume (mL or grams)

Number of cups

cup(s)

2. Brew Ratio

Ratio preset by brew method

Your Brew Recipe

Coffee Dose

grams

Water Needed
-
mL (= grams)

Ratio

coffee : water

Yield

mL brewed

Ratio Comparison Table

Cup size for this table (mL per serving; affects the comparison table only)

Ratio	Brew Style	Coffee (g) per cup	Water (mL) per cup	Strength

Your Brew Breakdown

Brew method preset-

Ratio-

Number of cups-

Coffee dose (total)-

Water needed (total)-

g coffee per 100 mL water-

Scaling Guide

Per 1 cup (250 mL)-

Per 2 cups (500 mL)-

Per 4 cups (1,000 mL)-

Per 8 cups (2,000 mL)-

Per 1 litre water-

g coffee per litre water-

Tip: Adjust the inputs above to see your brew recipe.

How the Coffee to Water Ratio Works

The coffee to water ratio is the single most important variable in brewing flavourful coffee. It is expressed as a ratio of coffee to water by weight, most commonly as 1:X where X is the number of grams of water for every gram of coffee. Because water weighs exactly 1 gram per millilitre at room temperature, the ratio works equally well using millilitres for water.

The formula is straightforward:

Water (mL) = Coffee (g) x Ratio
Coffee (g) = Water (mL) / Ratio

For example, with 18 g of coffee at a 1:16 ratio: Water = 18 x 16 = 288 mL.

SCA Golden Ratio and Recommended Ranges

The Specialty Coffee Association (SCA) recommends a brewing ratio of 55 grams of coffee per litre of water (1:18.2) as its "golden cup standard." In practice, most specialty coffee drinkers use ratios between 1:15 and 1:18. A lower ratio number (such as 1:12) produces a stronger, more concentrated brew. A higher ratio number (such as 1:18) produces a lighter, more delicate cup.

Ratios by Brew Method

Brew Method	Typical Ratio	Coffee per 250 mL	Notes
Espresso	1:2	25 g (for 50 mL yield)	Highly concentrated; usually 18-20 g in, 36-40 mL out
Moka pot	1:7 to 1:10	25-35 g	Use finely ground coffee; fill basket fully
AeroPress	1:6 to 1:15	16-40 g	Flexible; concentrate or full cup both common
French press	1:12 to 1:16	15-20 g	Coarse grind; 4-minute steep
Pour over (V60, Chemex)	1:15 to 1:17	14-16 g	Medium-fine grind; 3 to 4 minute brew
Filter / drip machine	1:16 to 1:18	13-15 g	Medium grind
Cold brew	1:7 to 1:10	25-35 g	Coarse grind; steep 12-24 hours; dilute before drinking

Worked Example

You want to make one 250 mL cup of pour over coffee at a 1:16 ratio:

Coffee dose = 250 mL / 16 = 15.6 g (round to 15 or 16 g)
Water needed = 15.6 g x 16 = 250 mL
Set your kettle to 92-96 degC and pour slowly in stages over 3 minutes

The calculator uses 18 g coffee as the default (common single-serve pour over dose). At 1:16, that requires 18 x 16 = 288 mL of water and produces approximately 250-270 mL of brewed coffee (some water is absorbed by the grounds).

Tips for Consistency

Always weigh your coffee and water in grams rather than using volume spoons. Ground coffee density varies significantly by roast and grind, so tablespoons are unreliable.
A digital scale with 0.1 g precision is the most important piece of brewing equipment after the grinder.
Water quality matters. Use filtered water. Mineral content (especially magnesium and calcium) affects extraction. Aim for water in the 75-250 ppm total dissolved solids range.
Water temperature for most methods should be 90-96 degC. Cooler water (around 85 degC) suits lighter roasts; hotter water suits darker roasts.
Grind size affects extraction speed. If your coffee is too bitter, grind coarser or reduce the ratio. If it is too sour or weak, grind finer or increase the coffee dose.

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Method: Water (mL) = Coffee (g) x Ratio; Coffee (g) = Water (mL) / Ratio. Water density taken as 1.000 g/mL at room temperature. Ratio presets based on Specialty Coffee Association brewing standards and widely published brew guides.

Ratios and brew parameters shown are general guidance based on widely accepted specialty coffee standards. Actual results depend on your specific coffee, grinder, water quality, and brew technique. Adjust to your taste.