The short answer for brewed coffee is 1 gram of coffee to 16 grams of water — a 1:16 ratio, which is about 60g of coffee per litre and sits inside the range the Specialty Coffee Association uses for its brewing standards. Start there for drip, pour over and French press. Cold brew is much stronger because it gets diluted (1:8 and up). Espresso is a different number entirely (about 1:2) because it is a concentrate, not a brewed cup. Everything below is the detail and the arithmetic.
One thing to get out of the way: weigh it, do not scoop it. A level tablespoon of whole beans and a level tablespoon of fine grounds contain very different amounts of coffee, and “one scoop per cup” is unreliable for the same reason — the same volume of a light roast weighs more than a dark roast, because darker beans are less dense. Volume measures are the single biggest source of inconsistency in home coffee, and a cheap scale removes it permanently.
The ratios, by method
Each of these is a working starting point, not a law. The ranges exist because roast level, grind and personal taste all move the right answer.
Drip / automatic coffee maker — 1:15 to 1:17.Call it 60g of coffee per litre of water. For a standard 12-cup machine, where the carafe markings are 5oz “cups” rather than 8oz mugs, that means roughly 10g of coffee per carafe cup. This is the method where people most often under-dose, because the scoop supplied with the machine typically holds less than the grounds the markings assume.
Pour over — 1:15 to 1:17, most often 1:16. A very common single-mug recipe is 22g of coffee to 350g of water, or 15g to 250g for a smaller cup. Pour over is also where ratio interacts most with technique: the same 1:16 brewed with a slow, even pour tastes different from a fast, sloppy one, so change one variable at a time.
French press — 1:12 to 1:15.Stronger than pour over, deliberately. A press has no paper filter, so more oils and fines stay in the cup, giving more body at the same ratio; and the immersion brew extracts less efficiently than a percolation brew, so a higher dose compensates. For a 34oz (1L) press, about 60–80g of coffee. Start at 70g and adjust.
Cold brew — 1:8 for a concentrate, 1:15 to drink as-is. This is the ratio people get wrong most often, because cold brew is usually made as a concentrate and then diluted 1:1 with water or milk when serving. If you follow a 1:8 recipe and drink it neat it will be overwhelming. If you want to brew it ready-to-drink, use roughly 1:15 and skip the dilution. Cold water extracts far less efficiently than hot, which is why the dose is so much higher and the steep so much longer.
AeroPress — 1:12 to 1:16, depending on the recipe. It brews as a concentrate that you can dilute, so both the strong-and-diluted and the brew-to-drink approaches work. A common starting point is 15g to 220g of water.
Moka pot — filled, not measured.The genuine exception. A moka pot is designed around its own geometry: fill the basket level with ground coffee without tamping, and fill the base to just below the safety valve. The pot sets the ratio, which lands in concentrated territory. Trying to impose a 1:16 ratio on one will not work, and if yours tastes harsh the problem is grind or heat rather than dose — see best coffee beans for a moka pot.
Espresso — 1:2, in about 25 to 30 seconds. Not a brewed-coffee ratio and not comparable to the numbers above: espresso is a concentrate produced under roughly 9 bar of pressure. The convention is called a brew ratio— an 18g dose yielding about 36g of liquid espresso. Shorter and more concentrated is a ristretto (around 1:1.5), longer is a lungo (1:3 or more). Full detail in how many grams of coffee for a double shot and ristretto vs lungo.
The arithmetic, so you can scale any of them
Every ratio above is the same calculation, and it works because 1 millilitre of water weighs 1 gram. So water volume and water weight are interchangeable, and you never need a separate measuring jug.
To find the coffee dose:divide the water weight by the second number of the ratio. For 500g of water at 1:16 → 500 ÷ 16 = 31g of coffee.
To find the water:multiply the coffee by the second number. For 20g of coffee at 1:15 → 20 × 15 = 300g of water.
Two practical cautions when you scale. First, mind what a “cup” means: a US customary cup is 8 fl oz (about 237ml), but the markings on a drip machine carafe are usually 5 fl oz (about 148ml), and a mug is commonly 10–12 fl oz. These are not the same unit and mixing them up is the most common reason a recipe comes out wrong. Second, the brewed coffee you pour will weigh less than the water you started with, because the grounds retain roughly two grams of water per gram of coffee. That retention does not change the ratio you dose at — always calculate from the water you add, not the coffee you end up with.
How to adjust, and in which direction
Ratio controls strength— how much dissolved coffee is in the water. Grind size and brew time control extraction— how much of each particle got dissolved. They are different problems with different symptoms, and confusing them is why people chase their own tail.
Weak and watery, but not sour:a strength problem. Use more coffee — move from 1:17 toward 1:15.
Sour, thin, and finishes quickly: under-extraction, not strength. Grind finer or brew longer. Adding coffee will make a stronger sour cup.
Bitter, harsh, drying: over-extraction. Grind coarser or brew shorter. Reducing the dose will not fix it, and it is the standard first wrong move.
Correct strength, boring: that is usually the beans or their freshness, not the ratio. The sour-versus-bitter diagnosis for espresso specifically is in why is my espresso sour or bitter, and the grind size chart is the other lever.
You need a scale, and it is the cheapest thing here
None of this works with a scoop. What you want is 0.1g resolution, a tare button and ideally a timer so you can track grams and seconds together. Any of the three below does the job; which one depends on whether you brew espresso, filter, or both.
Quick reference
Drip / coffee maker:1:15–1:17 · ~60g per litre · ~10g per 5oz carafe cup
Pour over:1:16 · 22g to 350g water for a large mug
French press:1:12–1:15 · ~70g for a 1L press
AeroPress:1:12–1:16 · 15g to 220g water
Cold brew concentrate: 1:8, diluted about 1:1 when served
Cold brew, ready to drink: 1:15, no dilution
Moka pot: basket filled level, base filled below the valve
Espresso:1:2 brew ratio · 18g in, ~36g out, 25–30 seconds
Three things that change the right number for you
Roast level.Dark roasts are less dense and more soluble, so they extract faster and taste stronger at the same ratio. If you switch from a light to a dark roast and keep everything else the same, expect a heavier cup — dialling the dose back slightly is a reasonable response.
Water, more than people expect. Mineral content affects how much flavour the water can carry out of the coffee, and water that is too soft makes a flat cup at any ratio. If your coffee tastes dull everywhere, look at what water to use before you blame the recipe.
The vessel you drink from.A recipe written for a 250g cup, poured into a 400ml mug and topped up, is no longer that recipe. Scale the whole thing with the arithmetic above rather than brewing the same amount and adding water — though deliberately adding hot water to a strong brew is itself a legitimate drink, which is what an americano is.
Why the numbers differ between methods at all
Two mechanisms explain almost every difference on this page. Contact style: percolation methods (drip, pour over) pass fresh water through the bed continuously, which extracts efficiently, so they need less coffee. Immersion methods (French press, cold brew) sit the coffee in a fixed body of water that gradually saturates, which extracts less efficiently per gram, so they need more. Temperature: hot water extracts far faster than cold, which is why cold brew needs both a much heavier dose and a steep measured in hours. The methods overview is coffee brewing methods.
