Coffee Ratio Calculator
Calculate the coffee or water amount needed for a given brew ratio, with results converted to grams, milliliters, and cups.
g
Result
Water Needed
320
grams
≈ ml / cups
320 ml / 1.35 cups
How to Use the Coffee Ratio Calculator
A brew ratio expresses how much water to use per gram of coffee grounds — a 1:16 ratio means 16 grams of water for every 1 gram of coffee. Pick a common brew ratio (or enter a custom one), choose whether you're solving for the water amount or the coffee amount, and enter the known value to get the other.
Coffee (g) = Water (g) ÷ Ratio
Since water's density is close enough to 1g per 1ml for kitchen purposes, the water weight in grams is also shown converted to milliliters and standard 8oz cups for convenience.
Example
At a 1:16 ratio, 20 grams of coffee needs 20 × 16 = 320 grams of water — about 320ml, or roughly 1.35 cups. A stronger 1:15 ratio would need only 300 grams of water for the same 20 grams of coffee, while a lighter 1:18 ratio would need 360 grams.
Common Use Cases
- Scaling a pour-over or drip coffee recipe up or down while keeping the same strength.
- Converting a favorite brew ratio between grams of coffee and grams/ml of water.
- Dialing in a personal preferred strength by testing different ratios against the same coffee dose.
FAQs
- What ratio should I start with? 1:16 is a widely used starting point for drip and pour-over coffee. Use 1:15 for a stronger cup or 1:17–1:18 for a milder one, then adjust to taste.
- Does the ratio change for espresso? Yes — espresso uses much tighter ratios (commonly around 1:2), well outside the drip-coffee presets here. This calculator is aimed at drip, pour-over, and immersion brewing ratios.
- Is 1 gram of water really equal to 1 milliliter? Very close — water's density is almost exactly 1g/ml at typical brewing temperatures, so using a kitchen scale in grams for both coffee and water gives you an accurate, repeatable measurement without needing a separate liquid measuring cup.