How Much Coffee per Cup of Water? Grams, Not Scoops

2026-10-15

How much coffee per cup of water? Weigh it: a good starting point is 1 gram of ground coffee for every 15 to 17 grams of water, which coffee people write as 1:15 to 1:17. For a 250 ml cup at 1:16 that's 15.6 g of coffee. For a big 360 ml mug brewed the way one US roaster's pour-over guide does it, at 1:15, it's 24 g.

That's the whole answer if you own a kitchen scale. The rest of this guide is about why the answers in most search results disagree with each other, sometimes inside the same article. It comes down to three slippery words: cup, scoop and golden.

How much coffee per cup of water, in grams

A brew ratio of 1:N means N grams of water for every gram of ground coffee. The Specialty Coffee Association defines the brewing ratio exactly this way, as brewing water per weight of ground coffee, and treats a millilitre of water as a gram. So:

• Coffee you need = water ÷ N.
• Water you need = coffee × N.
• The same ratio in grams per litre = 1000 ÷ N.

A few worked examples, all from published recipes:

• 200 ml of water at 1:16 needs 12.5 g of coffee.
• 250 ml of water at 1:16 needs 15.6 g.
• 24 g of coffee at 1:15 takes 360 ml of water, which is the V60 recipe from Equator Coffees.
• 100 ml of water at 1:10 needs 10 g, the usual starting point for Turkish coffee.

The lower N is, the stronger the coffee. 1:15 is stronger than 1:17. If your cup tastes thin, lower N by half a point or a full point. If it tastes heavy or bitter, raise it.

Why "a cup" is not a measurement

The first problem with the question is the word cup. It can mean a measuring cup, the cup marks printed on a coffee maker's water tank, or whatever mug you own. These are not the same amount of water.

The US National Coffee Association writes its rule per 6 ounces of water, not per mug. The cup marks on drip machines are smaller than most mugs and vary by brand, which even popular brewing guides warn about. Mugs come in every size.

Different authors pick different cups and then present their answer as the answer. That's how one recipe ends up with 12.5 g of coffee and another with 24 g, at nearly the same strength: the first is for 200 ml of water, the second for 360 ml. Measure the water you actually pour, in millilitres or grams, and the ambiguity disappears. A cup on your scale is simply a number.

Scoops and tablespoons: a built-in error of two to one

The second problem is the scoop. The National Coffee Association's own "Golden Ratio" is "1 to 2 tablespoons of ground coffee for every 6 ounces of water." Read that literally: at the top of the range you use twice as much coffee as at the bottom, and both count as golden.

Part of that spread is the spoon itself. How heaped it is, how fine the grind is and how dark the roast is all change how many grams fit in it. A volume measure can't carry a ratio precisely, so guides that convert between spoons and grams tend to trip over their own numbers.

One widely read guide shows the problem clearly. For a single 8 oz pour-over cup it recommends 15 to 16 grams of coffee. Further down, in its chart for brewing without a scale, the medium-strength 8 oz cup is 2 tablespoons, listed as 10 g. Same cup, same article, two clearly different strengths.

If you don't have a scale, a spoon will still make coffee. Just don't expect a spoon-based recipe to match a gram-based one, and keep the same spoon if you want repeatable cups. A kitchen scale that reads to 0.1 g is what coffee cupping protocols ask for, and it ends the guessing.

The golden ratio is a benchmark, not your recipe

Many articles say the "golden ratio" is 1:18 and stop there. The number does come from the SCA. Its Golden Cup benchmark is 55 g of coffee per litre of water, and the cupping protocol uses 8.25 g of coffee to 150 ml of water, roughly 1:18.

What usually gets left out:

• It's a range, not a point. The Golden Cup figure carries a tolerance of 10 percent either way.
• It's used for testing and certifying coffee brewers and for cupping, where professionals taste many coffees side by side under identical conditions. It isn't a claim that 1:18 is the best-tasting home brew.
• The SCA's own magazine gives a different everyday example for drip and immersion coffee: 60 g/L, which is a ratio of about 1:16.7.
• Roasters' home brew guides more often start at 1:15 to 1:17, and baristas in interviews talk about 60 to 65 g of coffee per litre.

Converting between the two ways of writing strength helps when recipes don't match. 1:18 is about 55 g/L, and 1:16 is 62.5 g/L. A recipe in grams per litre and a recipe in 1:N are the same thing written two ways, and either one is fine to start from.

Water in is not coffee out, and espresso is different

Every ratio above is written in terms of the water you pour, not the coffee you drink. Wet grounds hold back part of the water and a paper filter soaks up a little more, so the drink in your cup is smaller than the water you started with. There's no reliable published conversion factor for how much is lost. If you need a set amount in the cup, add some extra water and keep the same ratio.

Espresso doesn't fit this scheme at all. When a barista says 1:2, they're comparing the coffee dose with the weight of the drink that comes out, for example 18 g of coffee yielding 36 to 54 g of espresso. The SCA calls that a beverage ratio, as opposed to the brewing ratio used for filter coffee. Putting an espresso ratio into a brewing-ratio formula gives nonsense.

Turkish coffee is the other outlier. It's brewed much stronger than filter coffee, around 1:10, which is why a small 100 ml serving takes 10 g of very finely ground coffee.

Working out your own cup

Here's a routine that works for any brewer except espresso:

• Weigh or measure the water you'll actually pour, in millilitres.
• Pick a starting ratio: around 1:15 to 1:17 for pour-over, drip and French press, around 1:10 for Turkish coffee.
• Divide the water by N to get the grams of coffee.
• Brew, taste, and change N by 0.5 to 1 next time. Change one thing at a time.

The coffee to water ratio calculator below does that arithmetic in both directions. Enter the water and your ratio to get grams of coffee, or enter the coffee you have left in the bag to see how much water it needs. It also shows the same ratio in grams per litre, so you can compare a recipe written as 60 g/L with one written as 1:16.