Coffee Brew Ratio Calculator
Coffee Brew Ratio Calculator
Dose, water and yield for pour-over, drip, French press, immersion, AeroPress, cold brew and espresso — with the water the wet grounds keep taken out, so a 1:16 brew is shown as the 1:14 drink it actually is. Espresso handled as its own thing, because its ratio is dose to liquid out.
Coffee brew ratio
18 g of coffee brewed as a pour-over at 1:16, grounds keeping 2 g/g
The mass balance, which is the whole page
- dose
- dry ground coffee, by mass. Every ratio on this page is a mass ratio; a spoon is not a mass
- ratio
- for every method except espresso, parts of water IN per part of dry coffee. For espresso, parts of liquid OUT per part of dry dose — a different quantity with the same notation
- LRR
- liquid-retained ratio: grams of brew liquid the wet bed holds per gram of dry coffee. About 2 for drip and a plunger, about 3 for a full immersion, about 2 for an espresso puck
- water density
- 0.99821 g/mL at 20 °C, 0.95835 at 100 °C. A volume of water is only a mass once you say how hot it is
- extraction yield
- the share of the dry dose that ends up dissolved. The brewing control chart computes it from the beverage alone and so leaves out the solids in the wet bed
Worked example
18 g of coffee brewed as a pour-over at 1:16, grounds keeping 2 g/g
Water in = 16 × 18 = 288 g. That is the headline, and it is the number you set the scale to
The wet bed keeps 2 × 18 = 36 g of it
So the coffee in the cup is 288 − 36 = 252 g, not 288 — you lose 12.5% of the water you poured
Which means the ratio you actually drink is 1 : 14, not 1 : 16. The gap is the liquid-retained ratio, exactly
18 g in 288 g of water is 62.5 g/kg, against the SCA Golden Cup figure of 55 — a stronger brew than the standard specifies
At a measured 1.35% TDS the brewing control chart would report an extraction of 18.9%, but the solids in the wet bed bring the mass balance to 21.6%
Every method on this page, and what its ratio is a ratio of
| Method | Ratio this page opens with | What the ratio means | Liquid retained (g/g) | Ratio in the cup | Coffee per kg of water (g/kg) |
|---|---|---|---|---|---|
| Pour-over / filter cone | 1 : 16.00 | coffee → water in | 2.0 | 1 : 14.00 | 62.5 |
| Drip / batch brewer, at the SCA Golden Cup ratio | 1 : 18.18 | coffee → water in | 2.0 | 1 : 16.18 | 55.0 |
| French press / cafetiere | 1 : 13.00 | coffee → water in | 2.0 | 1 : 11.00 | 76.9 |
| Full immersion in a jug or cezve | 1 : 13.00 | coffee → water in | 3.0 | 1 : 10.00 | 76.9 |
| AeroPress | 1 : 14.00 | coffee → water in | 2.0 | 1 : 12.00 | 71.4 |
| Cold brew CONCENTRATE, to be diluted | 1 : 4.50 | coffee → water in | 3.0 | 1 : 1.50 | 222.2 |
| Cold brew, ready to drink | 1 : 12.00 | coffee → water in | 3.0 | 1 : 9.00 | 83.3 |
| Espresso — the ratio is dose to LIQUID OUT | 1 : 2.00 | dose → liquid out | 2.0 | 1 : 2.00 | 250.0 |
The two Golden Ratios do not agree, and the volumetric one cannot
| If a US tablespoon of your grounds weighs… | 1 tbsp per 6 fl oz is | 2 tbsp per 6 fl oz is | 1 tbsp per 6 fl oz, in g/kg | 2 tbsp, in g/kg |
|---|---|---|---|---|
| 3.0 g per US tbsp | 1 : 59.0 | 1 : 29.5 | 16.9 | 33.9 |
| 4.0 g per US tbsp | 1 : 44.3 | 1 : 22.1 | 22.6 | 45.2 |
| 5.0 g per US tbsp | 1 : 35.4 | 1 : 17.7 | 28.2 | 56.5 |
| 6.0 g per US tbsp | 1 : 29.5 | 1 : 14.8 | 33.9 | 67.7 |
What the two standards bodies actually specify
| Quantity | Figure | Document |
|---|---|---|
| Drip brew ratio | 55 g of coffee per 1.000 kg of fresh water (1:18.18) | SCA Standard 310-2021 |
| Brew strength | 1.15-1.55% TDS | SCA Standard 310-2021 |
| Slurry temperature | 90-96 °C | SCA Standard 310-2021 |
| Extraction yield thought desirable | 18-22% of the dry dose | widely published; Wikipedia, Coffee extraction |
| Pour-over ratio | 1:13 to 1:16 | National Coffee Association |
| French press ratio | 1:10 to 1:16 | National Coffee Association |
| Cold brew ratio | 1:4 to 1:5 — a concentrate, to be diluted | National Coffee Association |
| Bloom | water equal to double the dose, 30-45 s | National Coffee Association |
| Brew water temperature | 93 ± 3 °C | National Coffee Association |
| Liquid retained by the bed | about 2 mL/g drip, about 3 mL/g immersion | Barista Hustle ACM 5.03 |
| Certified Italian espresso | 7 ± 0.5 g of grounds, 25 ± 2.5 mL in the cup including crema, 9 ± 1 bar, 25 ± 5 s | Istituto Nazionale Espresso Italiano |
What this page will not do
| Asked for | Why not |
|---|---|
| Grind size in microns from a grinder setting | There is nothing publishable here. A grinder’s numbered setting is a position on that model’s own burr adjustment, and two grinders at “18” have no relationship at all — not even a monotonic one once you compare a conical burr with a flat one. Published micron figures for “medium” or “fine” are particle-size distributions with long tails, not single numbers, and the fines fraction that drives extraction is not captured by the mode. Nothing here converts. |
| A brew time | Time is an outcome of the grind, the bed depth and the pour, not an input you can convert to. The published contact times in the table above are the ones their publishers state for their own methods, and they are there as context, not as a conversion. |
| Caffeine content | It depends on the bean species, the roast, the dose and the extraction, and the figure people want is usually per cup rather than per gram. Nothing on this page measures it. |
| A water recipe (minerals, hardness, alkalinity) | A real and important subject, and a different one. For the hardness units themselves see the water hardness converter. |
Why 1:16 is not 16 parts of coffee
The ratio everybody quotes is not the ratio you drink. Publish a pour-over at 1:16 and you are describing dry coffee to water poured in. What comes out of the cone is that water minus whatever the soaked bed keeps, and the bed keeps a lot: Barista Hustle’s liquid-retained ratio is about 2 mL per gram of dry coffee for drip and a plunger, and about 3 for a full immersion in a jug or a cezve. So 18 g at 1:16 takes 288 g of water and gives 252 g of coffee — a drink at 1:14. Move the same recipe into a cafetière modelled as an immersion and you are at 1:13. The strength has not changed; the amount has, and that is why a recipe that fills a carafe in one brewer comes up short in another.
Espresso’s ratio is a different quantity with the same notation. A 1:2 shot means dry dose to liquid in the cup — 18 g in, 36 g out. To deliver those 36 g the machine has to push roughly 36 + 2 × 18 = 72 g of water through the puck, because the puck keeps about twice its own dry mass, so the water-in ratio is nearer 1:4. Quote a filter ratio as water in and an espresso ratio as liquid out and both are correct. Treat them as the same number and one of them is out by a factor of two, which is the single commonest error on this subject. It is worth knowing too that the Istituto Nazionale Espresso Italiano’s certified espresso is defined the old way, as 7 ± 0.5 g of grounds giving 25 ± 2.5 mL in the cup with the crema — a volume, measured in a glass, and not a 1:2 anything.
A volume of water is not a mass, and neither is a spoon of coffee. Water is 0.99821 g/mL cold from the tap and 0.95835 g/mL off the boil, so measuring a litre cold costs you 0.2% and measuring it boiling costs you 4.3% — a whole ratio point. Grounds are worse. The National Coffee Association’s own drip page gives the Golden Ratio volumetrically, as one to two tablespoons per six fluid ounces of water, and Trade Coffee measured a tablespoon of medium-roast grounds at 4 g and a dark roast at 3 to 3.3 g. Run those through the arithmetic and the same published rule spans about 1:15 to 1:59, while SCA Standard 310-2021 specifies 55 g of coffee per kilogram of water and nothing else. Two published standards for the same brew, and the one with a spoon in it is a factor of four wide.
Where the extraction number comes from, and what it leaves out. If you own a refractometer you measure strength — dissolved solids as a percentage of the beverage — and then compute extraction as strength × beverage mass ÷ dose. That is the brewing control chart, and it is a good instrument. But the beverage in it is only the liquid that reached the carafe: the liquid still in the wet bed is at the same concentration and carries dissolved solids that also came out of your dose. Put those back and at 1:16 with a retained ratio of 2 the extraction rises by about a seventh in relative terms. Both numbers are computed above. Neither is wrong; they measure different things, and the useful discipline is to pick one and use it every time.
What this page will not do. It will not convert a grinder setting into microns, because a grinder’s number is a position on that model’s own adjustment and two grinders on the same number are not making the same coffee — there is no conversion to build. It will not give you a brew time, which is an outcome rather than an input, and it will not estimate caffeine. For the kitchen arithmetic around it, see the cups to grams converter for ingredient densities, the US, UK and metric measures converter for the volume units themselves, and the recipe scaling calculator when you are making more of something.
Frequently asked questions
How much coffee for 500 mL of water?
At 1:16, 31.2 g — but read the question carefully, because 500 mL of water is 499.1 g at 20 °C, not 500, and 500 mL of coffee in the cup is a different question again. For 500 g of water at 1:16 you want 31.3 g of coffee and you will get about 437 g of drink, because the wet grounds keep the rest. Set this page to “I want this much coffee in the cup” if the 500 is what you want to drink.
Why doesn’t a 1:16 brew give me 16 parts of coffee?
Because the spent grounds keep some of the water. The liquid-retained ratio is about 2 g per gram of dry coffee for drip and a plunger and about 3 for a full immersion in a jug, so a 1:16 brew comes out at 1:14 in the cup and a 1:16 immersion at 1:13. The strength is unchanged — the same dissolved solids are in less liquid than you poured — but the amount is not, and that is why a recipe that works in a V60 comes up short in a cafetière.
Is espresso really 1:2?
Yes, and it means something different from every other ratio on this page. Espresso’s 1:2 is dry dose to liquid in the cup, so an 18 g dose gives 36 g of espresso — and to get that the machine has to push roughly 36 + 2 × 18 = 72 g of water through the puck, which is a water-in ratio of about 1:4. Quote a filter ratio as water in and an espresso ratio as liquid out and both are right; quote them as the same thing and one of them is out by a factor of two. Worth knowing as well: the Istituto Nazionale Espresso Italiano defines its certified espresso as 7 ± 0.5 g of grounds giving 25 ± 2.5 mL in the cup including crema — a volume, not a mass, and not a 1:2 shot.
What is the SCA Golden Cup ratio?
SCA Standard 310-2021 specifies the test brew as “55 g of coffee per 1.000 kg of fresh water”, which is 1:18.18. Two things about it are usually got wrong. It is stated per kilogram of water, not per litre of coffee, so there is no volume and no temperature in it. And 310-2021 puts its tolerance on the resulting strength — “a brew strength of 1.15-1.55%” — not on the ratio; the “55 ± 10% g/L” you often see is an older figure from a different document.
Do I need to weigh the water, or can I measure it?
You can measure it, as long as you know that a millilitre is not a gram. Cold from the tap water is 0.99821 g/mL, so a litre is 998.2 g and the shorthand is 0.2% high — irrelevant. Straight off the boil it is 0.95835 g/mL, so a litre of boiling water is 958 g and the shorthand is 4.3% high, which is a whole ratio point. Measure the jug cold, or weigh it.
Why does my refractometer say I am under-extracting when the coffee tastes fine?
Possibly because of the arithmetic rather than the coffee. The classic brewing control chart computes extraction as strength × beverage mass ÷ dose, and the beverage is only the liquid that reached the carafe. The liquid still in the wet bed is at the same concentration and carries dissolved solids too, and those came out of your dose. Put them back and the extraction rises — at 1:16 with a retained ratio of 2 the mass balance is about 14% higher relative than the chart figure. Both numbers are on this page; they are computed the same way every time, which is what matters for comparing one brew with the next.
What about grind size in microns?
This page refuses it, and the refusal is the honest answer. A grinder’s numbered setting is a position on that model’s own burr adjustment; two grinders on “18” are not making the same coffee and there is no conversion, not even a consistent ordering, between a conical burr and a flat one. Published micron figures for “medium” are particle-size distributions with long tails, and the fines that actually drive extraction are not described by the headline number. There is nothing here to convert.
Related calculators
References
- Specialty Coffee Association, SCA Standard 310-2021, Home Coffee Brewers (read 27 September 2026 from the copy hosted at coffeegeek.com), the current form of the Golden Cup standard and the anchor for the drip ratio here. It sets the test brew at “55 g of coffee per 1.000 kg of fresh water”, requires a brew strength of “1.15-1.55%”, and requires the slurry to “reach a temperature in the 90 to 96 °C range”. Note what it does and does not say: the ratio is stated per kilogram of water, not per litre of coffee, and 310-2021 puts its tolerance on the resulting STRENGTH, not on the ratio. The familiar “55 ± 10% g/L” is the older cupping figure and is not this document.
- National Coffee Association USA, brewing guides at aboutcoffee.org (read 27 September 2026), for the per-method ranges: pour-over “1 gram of coffee to 13-16 grams of water (1:13 to 1:16)”, French press “1:10 to 1:16”, cold brew “1:4 to 1:5”, water “93 ± 3 °C”, and a bloom of “water equal to double the coffee amount” for 30-45 s. Its drip page instead gives the volumetric Golden Ratio, “1 to 2 tablespoons of ground coffee for every 6 ounces of water”, which is a much weaker and much wider brew than 55 g/kg — see the table above, where both are computed.
- Barista Hustle, ACM 5.03 — Liquid Retained Ratios and the glossary entry liquid-retained ratio (read 27 September 2026): the ratio is “millilitres of brew liquid per gram of coffee”, and it is “approximately 3ml per gram of coffee” for immersion brewing (plunger, jug, cezve) against “around 2ml per gram” for drip. This is the single number that makes the yield come out right, and it is not one number.
- Blackout Coffee, My coffee is stealing my coffee: a few notes on absorption (read 27 September 2026), the same two figures from a second publisher, stated as “about 2x the dose” for press-style and “about 3x the dose” for a gravity-fed immersion carafe, with the worked example “20 g coffee holds about 40 g” and the honest caveat that these are “typical figures rather than fixed laws”.
- home-barista.com, A Note on Calculating Espresso Brew Ratios (read 27 September 2026), which states the trap this page is built around in one line: “we are using water in for brewing, and water out for espresso. Since the puck holds about twice its weight in water, this results in a large discrepancy.”
- Wikipedia, Espresso (read 27 September 2026), quoting the Istituto Nazionale Espresso Italiano’s certified-espresso parameters: “Necessary portion of ground coffee: 7 ± 0.5 g”, “Volume in cup (including crema): 25 ± 2.5 ml”, 9 ± 1 bar, 25 ± 5 s. The Italian definition is a volume in the cup; the modern specialty convention is a mass ratio. They are different quantities and this page prints both.
- Wikipedia, Coffee extraction (read 27 September 2026), for the extraction window “An extraction yield of 18% to 22% is desirable for most traditional coffee beverages” and the North American strength band “1.15% to 1.35%”.
- Trade Coffee, How to brew coffee without a scale (read 27 September 2026), the measured grams-per-tablespoon this page uses when a volume of grounds is entered: “4 grams per tablespoon pretty consistently within a few tenths of a gram for medium roasts, and between 3 and 3.3 grams for dark roasts”. The spread is why the volumetric route is shown with a warning and not as the default.
- Wikipedia, Properties of water (read 27 September 2026), quoting Tanaka et al. 2001 and the NIST Chemistry WebBook for VSMOW at 1 atm: 0.99984283 g/mL at 0 °C, 0.99704702 at 25 and 0.96188791 at 95. The Engineering ToolBox water-density table (read 27 September 2026) agrees to two decimals at every shared temperature and fills in the rest. The Tanaka closed form was re-evaluated here and reproduces the tabulated 0, 20 and 25 °C values to within 4 parts in 10 million.