What is the standard coffee-to-water ratio?

The Specialty Coffee Association (SCA) recommends 60 g of coffee per litre of water, which is a 1:16.7 ratio by weight. In practical terms, this means about 1 g of coffee for every 16 to 17 g (or ml) of water. This ratio is a starting point; personal taste, grind size, brew method, and coffee origin all affect the ideal ratio for a given cup.

How do I measure coffee and water accurately?

The most accurate method is to weigh both coffee and water in grams using a kitchen scale. Water weighs 1 g per ml at room temperature, so 200 ml of water weighs 200 g. Measuring coffee by weight (rather than scoops or tablespoons) accounts for variation in grind size and bean density. A medium-coarse grind for filter coffee weighs roughly 7 to 8 g per tablespoon, but this varies significantly.

Why does espresso use a different ratio to filter coffee?

Espresso extracts coffee under high pressure (around 9 bar) in 25 to 30 seconds, which produces a concentrated beverage. A standard espresso uses a ratio of about 1:2 (e.g., 18 g of coffee yields 36 g of espresso liquid). Filter methods such as pour over or French press use a much higher water-to-coffee ratio (1:15 to 1:17) because extraction relies on gravity and time rather than pressure, and the result is consumed as a full cup rather than a concentrated shot.

Coffee Ratio Calculator

This calculator works out the exact amount of coffee or water you need for any brew method, so every cup comes out balanced rather than too weak or too bitter. Start by choosing a brew method, pour over, SCA golden ratio, French press, AeroPress, cold brew concentrate, espresso or moka pot, each with its own standard ratio, or set your own custom ratio if you prefer. Then tell the calculator whether you know your coffee amount in grams or your water amount in millilitres, add a strength preference from much stronger to much lighter, and choose how many cups you are brewing. The calculator instantly returns the coffee needed in grams, the water needed in millilitres, the effective ratio expressed as 1:X, and the amount per cup, alongside a full brew breakdown and a method guide showing typical grind size, brew temperature and brew time. A table also scales your recipe across 1 to 8 cups so you can batch brew without doing the maths yourself. Because water weighs 1 g per ml at room temperature, grams and millilitres are interchangeable, and weighing your coffee on a kitchen scale rather than using scoops gives more consistent results. Use the tool to dial in your usual brew, try a new method with confidence, or scale a recipe up for guests, then adjust the strength setting to match your taste.

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Method verified 2026 Based on SCA brewing standards and standard brew ratios for common methods.

1. Brew Method and Ratio

Brew method (sets default ratio)

Custom ratio (1:X) e.g. 15 means 1 g coffee per 15 g water

: 1 coffee

Strength preference

2. Your Starting Amount

Choose whether you are starting with a known coffee amount or a known water amount.

I know my coffee (g)

I know my water (ml)

Coffee amount

Water amount

Number of cups

Your Brew Recipe

Coffee Needed
20.0 g
Grams

Water Needed
334 ml
Millilitres

Ratio (1:X)

1:16.7

Coffee to water by weight

Per Cup

20.0 g / 334 ml

g coffee / ml water

Ratios at Different Cup Counts

Cups	Approx Water	Coffee (1 cup base)	Total Coffee	Total Water

Brew Breakdown

Brew methodSCA golden ratio

Ratio (1 part coffee to X parts water)1:16.7

Strength adjustmentStandard

Effective ratio1:16.7

Number of cups1

Total coffee20.0 g

Total water334 ml

Method Guide

Typical grind sizeMedium

Brew temperature90 to 96 deg C

Brew time3 to 5 minutes

Coffee per tablespoon (approx)7 to 9 g

Approx tablespoons coffeeapprox 2.5 tbsp

Approx cups of water1.4 x 240 ml cups

Recipe: For 1 cup using SCA golden ratio (1:16.7), use 20.0 g of coffee with 334 ml of water. That is 20.0 g coffee and 334 ml water per cup.

How Coffee Ratios Work

A coffee ratio describes the proportion of coffee (in grams) to water (in grams or millilitres) used in brewing. Because water weighs 1 g per ml at room temperature, grams and millilitres are interchangeable for water in these calculations. The ratio is typically written as 1:X, where X is the number of parts water per part coffee. A ratio of 1:15 means 1 g of coffee for every 15 g of water.

Using weight rather than volume (scoops or tablespoons) gives consistent results because coffee density varies significantly depending on roast level and grind size. A kitchen scale accurate to 1 g is the best tool for repeatable results.

Standard Brew Ratios by Method

Method	Ratio (1:X)	Typical Coffee (per 250 ml cup)	Notes
Pour over / drip	1:16	15.6 g	Bright, clean cup. Medium grind.
SCA golden ratio	1:16.7	15 g	The Specialty Coffee Association standard for balanced filter coffee.
French press	1:15	16.7 g	Slightly stronger body. Coarse grind.
AeroPress	1:12	20.8 g	Concentrated. Fine to medium grind.
Cold brew concentrate	1:8	31.3 g	Brewed 12 to 24 hours. Dilute 1:1 to serve.
Espresso	1:2	N/A (18 g in, 36 g out)	High pressure extraction. Fine grind.
Moka pot	1:7	35.7 g	Stovetop espresso-style. Fine to medium grind.

Adjusting to Taste

The ratios above are starting points. If your coffee tastes too strong or bitter, increase the ratio (use less coffee or more water). If it tastes weak or watery, decrease the ratio. A ratio change of 1 (for example, from 1:16 to 1:15) makes a noticeable difference. Grind size, water temperature, brew time, and coffee freshness also affect extraction and perceived strength.

Worked Example

Using the SCA golden ratio (1:16.7) with 20 g of coffee and 1 cup:

Coffee: 20 g
Water: 20 x 16.7 = 334 ml
Ratio: 1:16.7
Per cup: 20 g coffee / 334 ml water

This matches the calculator's default output with 20 g coffee, SCA method, and 1 cup selected.

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Sources and method: Specialty Coffee Association (SCA) Brewing Standards (sca.coffee); Water and Coffee by Maxwell Colonna-Dashwood and Christopher Hendon (2015); standard brew guides from recognised specialty coffee educators. Ratios are by weight (g coffee to g water).

Ratios are by weight (grams). Water is treated as 1 g per ml. Brew time, grind size, water temperature, and coffee freshness all affect the final result. Adjust to personal taste.