Coffee Ratio Calculator Widget
A brew-ratio helper for coffee shops and home baristas: pick a method, enter the coffee you have or the water you want, and get the other side of the ratio, the strength in grams per litre and the volume in fluid ounces - with each preset labelled as a starting point rather than a rule.
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<iframe src="https://a2z.tools/embed/w/coffee-ratio-calculator" title="Coffee Ratio Calculator by A2Z Tools" width="100%" height="560" style="border:0;width:100%" loading="lazy" allow="clipboard-write"></iframe>
A plain iframe. Works everywhere, including site builders that strip scripts. Adjust height if your content needs more room.
<div data-a2z-widget="coffee-ratio-calculator" data-height="560"></div> <script async src="https://a2z.tools/embed.js"></script>
Adds a small script (what it does) that sizes the widget to fit its content, loads it lazily and keeps it isolated from your page's CSS.
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How it works
A brew ratio states how many grams of water are used for each gram of ground coffee. Water is weighed because 1 ml of water weighs about 1 g, so a scale replaces measuring jugs. At 1:16, 20 g of coffee needs 320 g of water; going the other way, 500 g of water at the French-press ratio of 1:15 needs 33.3 g of coffee. The drip preset uses 55 g of coffee per litre of water (about 1:18.2), the ratio commonly cited as the Specialty Coffee Association's Golden Cup recommendation; the Golden Cup target itself is a brew of 1.15-1.35% total dissolved solids at 18-22% extraction. Cold brew concentrate defaults to 1:5 and should be diluted before drinking. Espresso is different: its 1:2 compares the dry dose with the weight of drink in the cup, so 18 g in gives 36 g out. A custom ratio from 1:1 to 1:100 is accepted. Grams per litre is shown for every brewed method.
Calculation method
- Water (g) = coffee (g) x ratio; coffee (g) = water (g) / ratio
- Strength (g per litre) = 1,000 / ratio
- Espresso: beverage out (g) = dose (g) x ratio
- US fluid ounces = millilitres / 29.5735
Worked examples
Pour-over for one
Inputs: Pour-over 1:16; 20 g coffee
Result: 320 g (ml) water; 62.5 g per litre
About 10.8 US fl oz.
Golden Cup litre
Inputs: Drip 55 g/L; 1,000 ml water
Result: 55 g coffee
1,000 / 18.18 = 55.
Double espresso
Inputs: Espresso 1:2; 18 g dose
Result: 36 g espresso out
Dose to beverage weight.
Limitations
- Ratios are starting points; grind, roast date and water chemistry change the best recipe.
- The water figure is water poured, not the drink volume in the cup.
- Cold brew concentrate strength varies with steeping time, which the ratio alone does not capture.
Where publishers use it
- A specialty roaster's brew guides, one widget per method
- A cafe's barista-training handbook
- A home-coffee blog comparing brewers
- A coffee-equipment shop's product page for a pour-over kettle or scale
- An office-kitchen notice for the big batch brewer
Questions
What is the Golden Cup ratio?
The ratio most often quoted for the Specialty Coffee Association's Golden Cup is 55 g of coffee per litre of water, about 1:18. The standard's actual target is the result in the cup: 1.15-1.35% total dissolved solids at 18-22% extraction, the 'ideal' box of the classic brewing control chart.
Why weigh water instead of measuring cups?
Coffee cups differ in size and volume markings on brewers are rarely accurate. Weighing is exact, and because 1 ml of water is about 1 g, a gram reading on a scale is the volume in millilitres.
Are the presets standards?
No. 1:16 pour-over, 1:15 French press, 1:14 AeroPress and 1:5 cold brew concentrate are common starting points. Grind size, roast and taste move the best ratio; adjust in small steps, for example from 1:16 to 1:15 if the cup tastes thin.
How does the espresso ratio differ?
Espresso ratios compare the dry dose with the liquid espresso that comes out, not with the water used. A 1:2 ratio with an 18 g dose means stopping the shot at about 36 g in the cup. A ristretto runs nearer 1:1 to 1:1.5, a lungo 1:3.
Why is my cup smaller than the water I poured?
Wet grounds keep part of the water, and some evaporates. The widget reports water used, not the drink volume; expect noticeably less in the cup, especially with immersion brewers.
Sources
- Brew temperature, at fixed brew strength and extraction, has little impact on the sensory profile of drip brew coffee (Batali, Ristenpart and Guinard, Scientific Reports 10, 16450, 2020) - Scientific Reports (Nature Portfolio), open access . Describes the classic Coffee Brewing Control Chart and identifies its ideal region - 1.15-1.35% TDS and 18-22% extraction - as the Specialty Coffee Association's Golden Cup Standard. Checked 2026-10-01.
Cite or recommend this tool
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A2Z Tools Coffee Ratio Calculator https://a2z.tools/embed/coffee-ratio-calculator
<a href="https://a2z.tools/embed/coffee-ratio-calculator">A2Z Tools Coffee Ratio Calculator</a>
[A2Z Tools Coffee Ratio Calculator](https://a2z.tools/embed/coffee-ratio-calculator)
Coffee Ratio Calculator by A2Z Tools - https://a2z.tools/embed/coffee-ratio-calculator
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