How to use it
- Choose the Brew method.
- Choose what you I know the: water in millilitres or coffee in grams.
- Enter the Amount you know.
- Read the Ground coffee and the Water, and change Strength change only if you want a stronger or weaker cup.
How the ratio is worked out
A brew ratio is the grams of coffee for each litre of water. Multiply the water in litres by the ratio to get the coffee, or divide the coffee by the ratio to get the water. A strength change scales the coffee by its percentage, so +20 % takes 20 % more coffee for the same water.
coffee (g) = water (ml) ÷ 1000 × ratio (g per litre) × (1 + strength ÷ 100)
water (ml) = coffee (g) ÷ ratio (g per litre) ÷ (1 + strength ÷ 100) × 1000- Drip and pour-over: 55 g per litre, from the SCA Golden Cup protocol (8.25 g for 150 ml).
- French press: 60 g per litre, the most commonly written brewing ratio in SCA's 25 Magazine.
- Turkish coffee: 7 to 8 g per 70 ml cup, which the page takes as 7.5 g; the ratio is about 107 g per litre.
What this calculator does not cover
- Espresso, AeroPress and cold brew. No ratio from a source we could open was found for them, so they are not offered.
- Grind size, water temperature and brew time, which change the taste as much as the ratio does.
- Your coffee's own roast and freshness. A lighter roast may taste better at a different strength.
Worked example: 300 ml of water for drip
The SCA protocol uses 8.25 g of coffee for 150 ml of water. For 300 ml that is twice as much: 16.5 g of coffee. The ratio is 300 ÷ 16.5 = 18.2 g of water for each gram of coffee.
With a strength change of +20 %, the same 300 ml needs 16.5 × 1.2 = 19.8 g of coffee, and the ratio becomes 1 : 15.2.
| Brew | Water | Ground coffee | Ratio |
|---|---|---|---|
| Drip, standard | 300 ml | 16.5 g | 1 : 18.2 |
| Drip, +20 % strength | 300 ml | 19.8 g | 1 : 15.2 |
Frequently asked questions
How much coffee do I use for a litre of water?
For filter or drip coffee, the SCA protocol gives 55 g per litre, about 1 part coffee to 18 parts water by weight. French press uses 60 g per litre, and Turkish coffee about 107 g per litre.
What does the ratio 1 : 18 mean?
It means 18 grams of water for each gram of coffee. Enter a weight of coffee and the page gives the water in millilitres, which is close to grams for water.
How strong is a Turkish coffee cup?
A cup of 70 ml uses 7 to 8 g of Turkish coffee, so a cup is strong by design. Use the strength change to adjust it a little, but do not expect a weaker result than the cup allows.
Why does the SCA protocol call its figure a protocol and not a standard?
The SCA article that gives the figure calls it the Golden Cup protocol, so the page uses that name.
Can I brew espresso with this calculator?
No. We did not find a cited ratio for espresso, so the page does not offer that method.
Sources
- SCA: Exploring alternative brewing methods (the Golden Cup protocol, 8.25 g per 150 ml)
- SCA 25 Magazine, Issue 9: water and coffee acidity (brewing ratio of 60 g per litre)
- Wikipedia (Turkish): Türk kahvesi (7 to 8 g per 70 ml cup)
Figures and text last checked on Tuesday, November 10, 2026.