Coffee to Water Ratio Calculator: Grams, Tablespoons and Cups

Enter how much water your brewer holds and pick a method. You get the dose in grams and in level tablespoons, the ratio it came from, and the number almost no calculator shows you: how much coffee is left once the grounds have kept their share.

Before you enter a number: which cup?

The word does two different jobs in coffee and they differ by nearly half. The cup marked on a drip machine carafe or a French press is a 5 fl oz coffee cup, about 148 mL. The cup in a kitchen measuring set is 8 fl oz, about 237 mL. A twelve-cup carafe therefore holds about 60 fl oz, not 96, and a recipe written in measuring cups is asking for something else entirely.

Both are in the unit list below, so pick the one that matches where you read your number. If you are unsure which your machine means, fill the carafe to the four-cup line and weigh it: near 590 g means five-ounce cups, near 950 g means eight-ounce cups.

Water1,005 gWeighed, not measured by volume. Water is close enough to 1 g per mL that the two are interchangeable at kitchen scale.
Ratio used (1 part coffee to)15.0 parts water
Coffee67.0 g
Level tablespoons14.6 tbspLevel, not heaped, and only as good as the grind it was calibrated on.
Coffee scoops (2 tbsp each)7.3
Brewed coffee you get back871 mLGrounds keep about twice their dry weight in water and it never reaches the cup.
That is about this many 8 oz mugs3.7
Water to brew the coffee you have300 gWorking backwards from the dose in the last field - useful when a bag or a sachet decides the batch size for you.
Worked examples
ExampleWaterRatio used (1 part coffee to)CoffeeLevel tablespoonsCoffee scoops (2 tbsp each)Brewed coffee you get backThat is about this many 8 oz mugsWater to brew the coffee you have
8-cup French press (34 fl oz)1,005 g15.0 parts water67.0 g14.6 tbsp7.3871 mL3.7300 g
V60 pour over, 500 g water500 g16.0 parts water31.3 g5.9 tbsp2.9438 mL1.8320 g
12-cup drip machine, full carafe1,774 g17.0 parts water104.4 g19.7 tbsp9.81,566 mL6.6340 g
Cold brew concentrate, 1 litre1,000 g6.0 parts water166.7 g37.9 tbsp18.9667 mL2.8120 g
AeroPress, 200 g water200 g14.0 parts water14.3 g2.5 tbsp1.3171 mL0.7280 g
SCA cupping bowl, 150 mL150 g18.2 parts water8.3 g1.7 tbsp0.8133 mL0.6364 g
Brew ratios used by this calculator (parts water to 1 part coffee, by weight)
MethodGrindLighterStandardStronger
French pressCoarse171512
Pour overMedium-fine171615
ChemexMedium-coarse171615
Drip machineMedium181715
AeroPressFine-medium161411
Cold brew concentrateExtra coarse864
CuppingMedium-coarse18.1818.1818.18

One row here is a published standard and the rest are not. The cupping row is fixed by the SCA cupping protocol at 8.25 g of coffee per 150 mL of water, which is where 1:18.2 comes from; it is a measurement protocol written to make samples comparable between tasters rather than a recommendation about taste, which is why its three columns are identical. Every other row is the middle of the range that mainstream brewing guidance converges on, and those ranges are wide - printed French press guidance runs from roughly 1:12 to 1:17 and all of it makes coffee people enjoy. Treat the standard column as a starting point to move away from, not a target you have missed.

Weight of one level US tablespoon of grounds, by grind
MethodGrams per level tablespoon (g)
French press4.60
Pour over5.30
Chemex5
Drip machine5.30
AeroPress5.70
Cold brew concentrate4.40
Cupping5

These reflect the bulk density typical of each grind size: finer particles pack with less air between them, so a fine grind weighs more in the same spoon than a coarse one. They are the softest figures on this page and are offered with that warning attached - roast level moves them again, because a dark roast has lost more mass and expanded, and a heaped spoon carries something like 40 percent more than a level one. Anyone who needs the dose to be right should weigh it.

What each unit converts to
UnitMillilitres (mL)
Grams or millilitres1
US fluid ounces29.57
Cups marked on the brewer147.87
US measuring cups236.59
Litres1,000

Four of these five rows are definitions rather than measurements, and no source is claimed for them: a US fluid ounce is 29.5735 mL, and water is treated as 1 g per mL. The row that is not a definition is the brewer cup. The cup marked on a drip carafe or a French press is a 5 fl oz coffee cup, not the 8 fl oz cup in a measuring set, and manufacturers are not consistent about it - some European machines mark 125 mL, a few use 6 oz. Fill your carafe to the four-cup line and weigh it: about 590 g means five-ounce cups, about 950 g means eight-ounce cups, and anything else means the manufacturer chose their own.

Assumptions and limits

  • Water is weighed in grams and volume converts at 1 g per mL. Hot water is a little less dense than that, but the difference is smaller than the resolution of any kitchen scale.
  • Brewed yield assumes the grounds retain about twice their dry weight in water. Squeezing a filter or leaning on a plunger recovers a little of it, along with the fines and the bitterness that come with it.
  • Cold brew figures are for concentrate, not for a batch you drink as it comes. Most people dilute the result somewhere between one part water to one part concentrate and three to one - taste as you go, because the strength here is deliberately far from drinking strength.
  • The cupping row is a measurement protocol rather than a taste recommendation. It exists so that two people tasting the same coffee are tasting the same drink.
  • Espresso and the moka pot are deliberately absent. In both, the basket sets the dose and the equipment sets the water, so a ratio calculator would be answering a question you are not free to ask.
  • Tablespoons are US tablespoons at 14.8 mL, level rather than heaped. The gram weight behind each one moves with grind and roast, which is why the calculator prints the gram figure first.

Ratio sets strength. Grind sets flavour.

These are two separate dials, and mixing them up is the most common reason a cup refuses to improve. The ratio decides how concentrated the drink is: how much dissolved coffee is carried in how much water. The grind size and the contact time decide how much of the bean was dissolved in the first place, and that is what the words bitter and sour are describing.

The practical consequence is that the instinctive fix is often the wrong one. A cup that tastes harsh and drying is usually over-extracted, and using less coffee makes it worse - the same volume of water now has fewer grounds to work on and pulls harder on each one. Grind coarser or brew shorter instead. A cup that tastes thin and sharply sour is under-extracted, and adding coffee will not sweeten it; a finer grind or a longer brew will.

So: change the ratio when the coffee tastes right but is too weak or too intense. Change the grind when it tastes wrong. Changing both at once tells you nothing, because you cannot tell afterwards which one moved.

You get back less than you poured in

Grounds keep roughly twice their own dry weight in water, and they keep it whether you are pouring through a filter or pressing a plunger. That water never reaches the cup, so the brewed volume is always short of what went in - and because the shortfall scales with the dose, the stronger the ratio, the bigger the gap.

At a pour over ratio the loss is easy to ignore: 500 g of water against about 31 g of coffee gives roughly 438 mL in the carafe. At cold brew concentrate strength it stops being a rounding error. A litre of water against 167 g of coffee gives back about 667 mL, which means a third of what you poured is still in the grounds. That is the whole explanation for why a cold brew batch always looks as though it shrank.

The calculator reports this as the brewed yield. If you are brewing to fill a particular flask or carafe, work from that number rather than the water figure, or you will come up a mug short every time.

Tablespoons are the least reliable number on this page

Weight is a property of the coffee. Volume is a property of the coffee and of how it was ground, how darkly it was roasted, and how the spoon was loaded. A level tablespoon of coarse French press grounds weighs about 4.6 g; the same spoon of fine AeroPress grind holds nearer 5.7 g, because smaller particles pack with less air between them. Dark roasts are less dense than light ones, having lost more mass and expanded in the process. And a heaped spoon carries something like 40 percent more than a level one.

Stack those together and the spoon figure can be out by a quarter in either direction. It is in the calculator because it is the only measure most kitchens have, not because it is good. A scale that reads to 0.1 g costs less than two bags of the beans it is measuring and removes every one of those variables at once.

If you are staying with spoons, keep them level and stay with the grind you calibrated on. Consistency in the wrong unit still beats inconsistency in the right one.

Where these numbers come from

It is worth being explicit about which of these figures is a standard and which is a convention, because only one of them is a standard. The cupping row is fixed by the SCA cupping protocol at 8.25 g of coffee per 150 mL of water, and that is where 1:18.2 comes from. Select cupping, enter 150, and the dose comes back at 8.3 g - the protocol figure, rounded to the tenth this page prints. If it ever returns something else, the table has been edited wrongly.

Every other ratio is the middle of a range that mainstream brewing guidance converges on rather than a number anyone has ruled on, and those ranges are wide. The standard column is a place to start from, not a target you have missed, and the lighter and stronger columns exist because moving away from it is the normal thing to do.

The gram-per-tablespoon column reflects the bulk density typical of each grind size, and the section above explains why it should be treated as the softest figure here. The unit conversions are definitions and are not sourced to anyone, with the single exception of the brewer cup, which is a manufacturer convention and is the reason this page opens with a warning about it.

Frequently Asked Questions

How much coffee do I need for a 12-cup coffee maker?
About 104 g, or roughly 20 level tablespoons, at a standard drip ratio. The figure surprises people because a 12-cup carafe means twelve five-ounce cups - around 1.77 litres - and not twelve mugs. Many machine manuals suggest one tablespoon per cup, which works out near 1:28 and is the usual reason a full pot tastes thin.
How many tablespoons is 20 grams of coffee?
Between about 3.5 and 4.3 level tablespoons depending on the grind: nearer 4.3 at a coarse French press grind, nearer 3.5 at a fine AeroPress grind. There is no single answer, which is the honest reason to weigh coffee rather than scoop it.
What is the golden ratio for coffee?
The phrase usually points somewhere between 1:15 and 1:18 - one gram of coffee to fifteen or eighteen grams of water. It is a useful default rather than a rule, and it does not travel: cold brew concentrate sits near 1:6 and espresso near 1:2, and neither is doing anything wrong.
My coffee is bitter. Should I use less coffee?
Usually not. Bitterness points at over-extraction, and cutting the dose makes the water work harder on what is left. Grind coarser or shorten the brew first, and change the ratio only once the flavour is right and the strength is not.
Does the ratio change for a dark roast?
The weight-based ratio does not need to, but the scoop does. Dark roasted beans have lost more moisture and expanded, so they are less dense, and the same tablespoon holds noticeably less coffee than it would of a light roast. It is another reason the gram figure is the one to trust.
Why are espresso and the moka pot not in the list?
Because you do not choose their ratio. The espresso basket sets the dose and you steer the drink with grind and yield instead; on a moka pot the basket and the safety valve fix both numbers for you. A ratio calculator would be offering you a choice the equipment has already made.