The Specialty Coffee Association’s Golden Cup standard is roughly 1:18 by weight; many people prefer 1:15–1:17.
How to use the Coffee to Water Ratio Calculator
- Coffee
- Ratio (coffee : water)
- Want to work backwards? Type a value into Water and Coffee is calculated for you.
Results update as you type, and every field accepts the units shown in its menu.
How it works
Multiply the coffee dose by the ratio to get the water weight (1 g of water ≈ 1 mL).
Inputs explained
| Field | What to enter |
|---|---|
| Coffee | Units: g, oz |
| Ratio (coffee : water) | Choose one: 1:15 (strong), 1:16 (balanced), 1:17, 1:18 (light) … |
What each result means
- Water = [Coffee]×[Ratio (coffee : water)]
- Brewed cups (≈240 mL) = [Coffee]×[Ratio (coffee : water)]×0.9÷240
Example values
How the main result changes when Coffee changes and everything else stays at the example values above:
| Coffee (g) | Water (g / mL) |
|---|---|
| 10 | 160 |
| 15 | 240 |
| 20 | 320 |
| 25 | 400 |
| 30 | 480 |
| 40 | 640 |
Formula
Water = coffee × ratioCoffee = water ÷ ratioWorked example
Inputs — Coffee: 20 g; Ratio (coffee : water): 1:16 (balanced).
Results — Water = 320 g / mL; Brewed cups (≈240 mL) = 1.2.
Frequently asked questions
Why weigh coffee?
Scoop volume varies with grind and bean, so grams give consistent results.
Why do I get less coffee than water used?
Grounds absorb about twice their weight in water.
What formula does the Coffee to Water Ratio Calculator use?
Water = coffee × ratio.
Can I work backwards from the result?
Yes. Type the result you want into Water and the calculator finds the matching coffee.