Coffee Ratio Calculator

Calculate the perfect coffee-to-water ratio for any brew method. From espresso to cold brew, get precise measurements in grams or ounces for consistent results every time.

Calculator
Presets:
1:1 Strong 1:20 Light
Metric (g/ml) Imperial (oz)

Results

cups (~250 ml)
Coffee
Water

1 : ratio

Common Brew Ratios

醸造方法 比率 Coffee per 250 ml 挽き目
Espresso 1:2 18 g (for 36 ml) Very fine
Moka Pot 1:7 35.7 g Fine
AeroPress 1:12 20.8 g Medium-fine
French Press 1:15 16.7 g Coarse
Pour Over 1:16 15.6 g Medium
Drip / Batch Brew 1:17 14.7 g Medium
SCA Gold Cup 1:18 13.9 g Medium
Cold Brew 1:8 31.3 g Extra coarse

How to Use

  1. 1
    Enter water amount

    Type the amount of water you plan to use, in milliliters or ounces.

  2. 2
    Choose your ratio

    Select a brew method preset or enter a custom coffee-to-water ratio.

  3. 3
    Get your measurement

    Read the exact amount of coffee grounds needed in grams or ounces.

About

The science of coffee brewing ratios was formalized by the Specialty Coffee Association (SCA), which established the Gold Cup standard through decades of research. The SCA recommends 55 g of coffee per liter of water (approximately 1:18) for optimal extraction between 18-22%.

Extraction is the process of dissolving solubles from ground coffee into water. Under-extraction (too little coffee or too short a brew) produces sour, thin coffee. Over-extraction (too much coffee or too long) yields bitter, astringent flavors. The ratio controls the concentration of the final brew.

Different brew methods require different ratios because of their varying contact times and filter mechanisms. Espresso forces water through fine grounds in 25-30 seconds at 9 bars of pressure, requiring a concentrated 1:2 ratio. Cold brew steeps for 12-24 hours, allowing a 1:8 ratio to produce a smooth, low-acid concentrate.

FAQ

What is the golden coffee ratio?
The Specialty Coffee Association (SCA) recommends a 1:16 ratio as the golden standard -- 1 gram of coffee for every 16 grams (ml) of water. This produces a balanced cup with good extraction.
How does the ratio affect coffee strength?
A lower ratio (1:12) produces stronger coffee with more body, while a higher ratio (1:18) yields a lighter, more delicate cup. Espresso uses an extremely low ratio of 1:2.
Should I measure coffee by weight or volume?
Weight (grams) is significantly more accurate. Coffee beans vary in density -- a scoop of light roast beans weighs more than the same scoop of dark roast. A kitchen scale is recommended.
How does grind size relate to ratio?
Finer grinds extract faster, so they work with shorter brew times and less water (like espresso). Coarser grinds need more water and longer brew times (like cold brew at 1:8).
What is TDS in coffee?
TDS (Total Dissolved Solids) measures the concentration of extracted coffee solubles. The SCA target is 1.15-1.35% TDS, achievable with a 1:15 to 1:17 ratio and proper extraction time.