Good coffee is mostly arithmetic: a consistent ratio of coffee to water, measured by weight. Pick pour-over, French press, AeroPress, drip, cold brew, Moka pot, or espresso and this calculator loads a sensible ratio range, then solves in whichever direction you need — coffee for the water in your kettle, water for the beans you have left, or both for a number of cups. Espresso is handled by yield, the way baristas actually dial it in.
Everything runs in your browser. Need to convert ounces or cups to milliliters for another recipe? The unit converter handles it, the countdown timer keeps your steep honest, and if you are baking something to go with it, try the sourdough calculator. Why pour-over, French press, and cold brew use such different ratios is explained in coffee-to-water ratios by brew method.
Frequently asked questions
What is the best coffee to water ratio?
For filter coffee, most specialty roasters' brew guides land between 1:15 and 1:18 — 1 gram of coffee for every 15 to 18 grams of water — and the Specialty Coffee Association's brewing standard specifies 55 g per litre, which is about 1:18. 1:16 is a good default for pour-over and drip. Immersion methods like the French press taste best a little stronger (1:12 to 1:15), and cold brew concentrate is much stronger (1:4 to 1:8) because you dilute it afterward. Start in the middle of your method's range and move one step at a time.
How many grams of coffee per cup?
It depends on the cup. A standard 8 oz (237 ml) cup at 1:16 needs about 17 grams of coffee once you account for the water the grounds soak up, while a 6 oz coffee-maker cup needs about 13 grams. Use the Number of cups mode: pick your cup size and the calculator adds back the roughly 2 grams of water each gram of grounds retains, so the finished coffee actually fills the cups you asked for. Coffee-maker carafes usually mark 5 to 6 oz cups, not 8 oz mugs.
How many tablespoons of coffee is that?
A level tablespoon of ground coffee weighs roughly 5 to 6 grams, depending on how fine the grind is and how dark the roast. The calculator converts using 5.5 grams, so treat the tablespoon figure as approximate. A standard coffee scoop is two tablespoons, or about 10 to 12 grams. If you want the same cup every morning, weighing with a kitchen scale is far more consistent than spoons. Scoops also vary between brands, so check yours once against a scale if you plan to keep using it.
Why is espresso measured by yield instead of water?
An espresso machine pushes water through the puck until you stop the shot, so the water you put in is not what you measure. Baristas instead weigh the dose of dry coffee and the liquid espresso that comes out. A 1:2 ratio — 18 grams in, 36 grams out — is the modern standard. Shorter ratios around 1:1 to 1:1.5 are ristretto-style, and longer ones around 1:3 are lungo. Because the yield includes dissolved coffee and crema, weigh it on a scale under the cup rather than reading the markings on a shot glass.
How do I make my coffee stronger or weaker?
Move the strength slider toward Stronger to use less water per gram of coffee, or toward Milder for more. If coffee tastes sour or thin even at a strong ratio, the grind is probably too coarse or the brew too short; if it tastes bitter and harsh, grind coarser or shorten the brew. Ratio controls strength, while grind and time control extraction, so change one variable at a time. Keep notes on what you changed so you can repeat a cup you loved.