Your morning coffee shouldn’t be a coin flip. If it’s great one day and undrinkable the next, you’re not dealing with bad beans or a faulty machine. You’re brewing blind. The key to consistency is mastering the the so-called “golden ratio,” the coffee industry’s baseline standard for precisely extracting the perfect amount of flavor from your grounds every single time.
Mastering this ratio means you will finally stop wasting money on premium beans only to ruin them with brewing guesswork. You’ll know exactly how much coffee and water you need to replicate that perfect cup on command-or adjust it deliberately when you want something stronger or lighter.
Once you start following this proven standard, your morning coffee will never be the same.
For a deeper understanding of the variables that influence coffee brewing, I spoke with java expert Kaleena Teoh, director of education for Coffee Project New York.
Teoh’s advice applies to those using a drip coffee maker, French press or pour-over system, learning the basics of balance will set your course for better coffee.
(Editor’s Note: If you’re using K-cups or another pod-based coffee system, the ratio is controlled by the machine, so this lesson doesn’t apply. And those brewing espresso have a slightly different set of brewing standards to consider.)
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What is the golden ratio?
If you’re aiming for the golden ratio, use one ounce of coffee for every 15 or 16 ounces of water.
The so-called Golden Ratio refers to the ideal proportions of water and ground coffee at the beginning of the brewing process, resulting in a full-flavored, balanced cup.
“The Specialty Coffee Association, an international organization that pretty much governs the guidelines that we use, suggests between a 15-to-1 to 20-to-1 ratio,” Teoh said. “It literally refers to the amount of water versus the amount of coffee grounds. And then the resulting volume at the end might vary entirely depending on what kind of system it is (whether automatic drip, French press, or pour-over).”
The golden ratio is based on weight, not volume
It’s worth noting that this ratio is based on weight, not volume. While coffee scoops may be calibrated for a particular grind size for a specific type of machine, the ratio’s effectiveness relies on a more precise measurement. A tablespoon potentially holds a different weight of coffee, whether you’re talking about fine espresso powder, conventional preground coffee or coarse cold brew grounds.
The goal of this precise ratio is flavor, with the appropriate strength to taste the actual coffee without elevated acidity, which reveals under-extraction, or astringency, which reveals over-extraction, and that can support additions like milk or sugar.
“Personally, I do a 16-to-1 ratio,” said Teoh, “which is frequently touted as the ideal within the 15- to 20-range. I think it’s nice, not too strong, and a good place to start.”
That ratio would ensure you taste the coffee even if you add stuff.
The higher the number in the ratio, which represents water, the gentler (or weaker) the resulting brew. So, if you take your coffee black, you may consider a slightly different ratio, like 18-to-1. If you drink it light and sweet, you might try a 15-to-1 ratio for a stronger coffee.
Other factors influence how effective the ratio is
There is no shortage of nuance when it comes to brewing coffee.
The ratio alone isn’t enough to ensure an optimal cup. The following elements also play a significant role in the outcome of brewed coffee.
Grind size
The size of the grind plays a vital role in how coffee is extracted. Conventional, pre-ground coffee typically has a “medium” grind tailored for most drip coffee machines, but that isn’t always appropriate across all methods. According to Teoh, a French press typically requires a coarser grind, “like sea salt,” whereas pour-over can benefit from a slightly finer grind than what you can find on supermarket shelves.
Temperature
Water should hit ground coffee at anywhere between 195 to 205 Fahrenheit.
Temperature also impacts how coffee is extracted. “The moment the water hits coffee, it will start extracting, whether it’s cold or hot,” said Teoh.
Cold brew is its own magical thing, of course, but when it comes to hot coffee, there’s an ideal temperature range, and — news flash — it isn’t boiling.
The SCA suggests temperatures between 195 to 205 Fahrenheit, or temps allowing extraction to maximize certain flavor compounds in the coffee, while still maintaining an appropriate temperature to drink, she said.
Agitation
Agitation refers to the movement of the grounds during extraction. “The more agitation you give it when coffee is being extracted, the more concentration occurs during brewing,” said Teoh. Agitation is limited in standard machines for brewed coffee but plays a role in French press and pour-over methods.
Suppose you’ve experimented with various drip coffee machines and coffee grounds and have always been a little underwhelmed with the results. In that case, it may be time to consider getting nerdy with something like pour-over, which can be fussy, but can help with this aspect of the brewing process.
Filter
The filter you use has a significant impact on the final result.
The filter you use is the final barrier between what’s happening during the extraction process and what arrives in your cup.
“Different filters have different pore sizes, allowing certain elements to pass through or not,” Teoh said. “Metal filters will allow for all solubles and some insolubles, while a paper filter will be able to hold back all of those insolubles, giving you a very clean cup.”
Insolubles may refer to minute granules of ground coffee and natural oils present in coffee.
One is not necessarily better than the other; it is a matter of preference. Oil can give coffee additional body, but it isn’t necessarily always desirable for everyone, either visually or texturally, she said.
Best practices from a coffee expert
To achieve the most out of the golden ratio, Teoh suggests practices that can make a noticeable difference in your daily brew.
Measurement
To nail the golden ratio, use weight instead of volume to measure your coffee.
The golden ratio relies on weight, so a scale is recommended to achieve that ideal 16-to-1 water balance to coffee grounds.
“Everything is being weighed in most coffee shops to ensure that there’s some sort of consistency,” Teoh said, noting that applies to the grounds, the water and, in the case of espresso, the resulting brew.
If you’re serious about upping your coffee game, a scale is an essential investment, and it doesn’t have to be an expensive one.
Barring that, “any unit of measurement that makes sense to the brewer, to have some sort of consistency through the brew day to day is better than nothing,” Teoh said.
This is bad news for the “eyeball it” method, but good for those where a kitchen scale is just one gadget too many, she said. However, if you’re committed to measuring by volume, whether with a tablespoon or coffee scoop, Teoh advises experimentation and precision to determine the best outcome for you.
Coffee quality
Naturally, a better cup of coffee also starts with better coffee, no matter the measurement system.
“Fresh beans will always taste better,” Teoh said, advising care when getting freshly roasted coffee.
Look at tasting notes, speak to the roastery staff, and taste different blends to determine if you like something bright and acidic, as with a light roast coffee, or more floral and fruity notes, as with a darker roast, she said.
Grinder
A burr grinder is a worthy good investment, according to Teoh.
More so than the scale, and even more so than the coffee maker itself, Teoh advises one device that can really affect the quality of your coffee.
“The best investment is actually the grinder,” she said. “Get a coffee machine that can do its job. It doesn’t have to be the most expensive one. But a burr grinder is actually an excellent investment.”
Ideally, as with a cheaper model, you want a grinder with settings that take the guesswork out of determining how fine the grind is.
“If you’ve just been buying pre-ground coffee, and you moved on to grinding it fresh, you will see quite a big difference in the cup,” Teoh said.
Consistency
Finally, the most crucial factor combined with all of the above is consistency, and not committing yourself to products or processes that you can’t follow through with regularly.
“Just use a method that is convenient to you, and that you’re able to use every day, because if it’s too much and too complicated, you’ll end up stopping,” she said.
“Pick something that you’re comfortable with and can do consistently,” whether with a particular ratio, particular beans, or particular devices, said Teoh. “And then play with it. Experiment with it until you find something that you like.”
