Introduction:Many beginners who are new to pour over coffee often face a common challenge: how to adjust the coffee-to-water ratio to brew a cup that is neither too weak nor overly bitter. In fact, mastering the correct ratio is key. From pour over to cold brew, different brewing methods have their own optimal ratio ranges. This article will provide a detailed breakdown of the concept of coffee-to-water ratios, the Golden Cup extraction theory, and practical guidance on choosing the right ratio for your brew—helping you easily achieve your desired flavor profile.

Brewing coffee without adding sugar or milk to create a uniquely flavorful and smooth cup is not easy for many newcomers. Too much water results in a weak and bland cup, while too little can make it overly strong or even bitter. Therefore,the coffee-to-water ratiobecomes especially important to master.

So, how much water should you actually use to brew a cup of coffee?What is the coffee-to-water ratio?This is a common question among beginners, who also wonder why recommendations from different cafés might vary slightly—for instance, some advocate for a 1:15 ratio. What’s the reason behind this?

First, we need to clarify two important concepts:the coffee-to-water ratioandcoffee grounds absorption rate.

The coffee-to-water ratiorefers to the proportion of coffee grounds to the water used for brewing. For example, a 1:15 ratio means for every 1 part of coffee grounds, 15 parts of water are used. If you’re using 15 grams of coffee, you would add 225 grams (or milliliters) of water.

Next is thecoffee grounds absorption rate. Generally, during the brewing process, coffee grounds absorb about twice their own weight in water (the actual figure may vary slightly). That means the final yield of brewed coffee is not equal to the amount of water you actually pour in. For a 1:15 ratio, the coffee grounds will absorb approximately 2 parts of water, so the resulting brewed coffee will be around 13 parts.

To help us understand which coffee-to-water ratios can produce balanced-flavor brews, we can refer to theGolden Cup extraction theoryproposed by the SCA (Specialty Coffee Association). This theory, based on the taste preferences of Western consumers, offers a widely accepted reference model through the relationship between coffee concentration and extraction yield.

According to the SCA Golden Cup standard, the ideal extraction range is:extraction yield of 18%–22%,concentration of 1.15%–1.45%. Coffee falling within this range is considered to have harmonious flavors and satisfying mouthfeel (note: this is the "good" as defined by the Golden Cup system, but may not align with everyone’s personal taste).

From the Golden Cup extraction chart, we can see that the coffee-to-water ratio range generally falls between 1:14.3 and 1:20.9 . Among these,1:17 a certain ratio 1:16 and 1:18are considered relatively easier to hit the Golden Cup zone, while 1:15 others

are more challenging to consistently stay within the Golden Cup range. 1:15 So, why do many brewing recommendations still suggest using

a specific ratio1:16–1:18 as the ideal coffee-to-water range? 1:15 From the perspective of Golden Cup theory,

a certain ratio 1:15 is indeed an ideal range. However, in practice, if you increase the ratio to 1:18, although the concentration and extraction may meet Golden Cup standards, it can easily lead to uneven extraction or less enjoyable flavors—especially when it comes to controlling extraction yield. Therefore, many baristas opt for the more conservative 1.35%–1.42% 1:15 or 1:16 17.79%–18.73%ratios.1:15 One coffee brand conducted multiple brewing experiments on light roasted coffee and found that when using

a 1:15 ratio

, the coffee concentration typically falls between 1:18.181.25%–1.35%

, with an extraction yield ofaround 18%–19%. Although these values are only at the edge of the Golden Cup standards, sensory evaluation showed that this ratio not only delivered good flavor performance, but also helped avoid common issues of under-extraction such as excessive acidity or astringency. This ratio is suitable for most coffee beans, and compared to larger coffee-to-water ratios that are more likely to cause over-extraction and bitterness,

The above content is compiled by CoffeeHunters, a coffee news website.