The Brew Coffee Brew Ratio Calculator
Stop guessing with scoops. Enter how much coffee you want to brew and your target ratio, and get the exact coffee dose in grams and tablespoons.
How to use this calculator
Pick a direction: either tell the calculator how much water you're brewing with and it will give you the coffee dose, or tell it how much coffee you have and it will give you the water. Enter the amount in millilitres, cups, or ounces, then set your ratio with the slider or tap a preset for your brew method. The result shows grams (the accurate way, with a kitchen scale) and tablespoons (the close-enough way, when you're traveling and forgot the scale).
Water and coffee weigh almost the same — one millilitre of water is one gram — so a 1:16 ratio simply means 16 grams of water for every 1 gram of coffee. That's why ratios scale perfectly: find the ratio you like once, and it works for a single mug or a full 12-cup pot.
The math, explained
The formula is division, nothing more. Coffee dose equals water divided by the ratio number: 500 ml of water at 1:16 needs 500 ÷ 16 = 31.25 grams of coffee. Going the other way, water equals coffee times the ratio: 30 grams of coffee at 1:16 needs 480 ml of water. The tablespoon conversion uses 10.5 grams per tablespoon of ground coffee, which is the widely used average — it varies a little with grind size and roast, but it's fine for everyday brewing.
Why grams instead of scoops? Because a "tablespoon" of coffee can weigh anywhere from 7 to 12 grams depending on the grind and how heaped it is. A scale is the single biggest upgrade most home brewers can make, and they're cheap — any $15 kitchen scale that reads in grams will do.
Tips for dialing in your ratio
Start at 1:16 and adjust to taste. If your cup tastes sour, sharp, or weak, your coffee is likely under-extracted — try a stronger ratio like 1:15, or grind finer. If it tastes bitter, dry, or harsh, you're over-extracting — move to 1:17 or grind coarser. Change one variable at a time so you know what fixed it.
Match the ratio to the method. Immersion brewers like the French press are forgiving, so 1:14 to 1:15 gives a full-bodied cup. Pour-over and drip shine around 1:15 to 1:17 where clarity matters. Espresso lives in a different world at 1:2 — it's a concentrate, not a cup of coffee.
Common brew ratios by method
| Method | Typical ratio | Notes |
|---|---|---|
| Espresso | 1:2 | 18 g in, ~36 g out for a double shot |
| Moka pot | 1:10 | Strong, concentrated stovetop brew |
| French press | 1:14 – 1:15 | Full immersion, coarse grind |
| Pour-over | 1:15 – 1:17 | Clean, bright cups |
| Drip machine | 1:16 – 1:17 | Set-and-forget balanced |
| AeroPress | 1:13 – 1:15 | Versatile, great for one cup |
| Cold brew concentrate | 1:4 – 1:5 | Dilute 1:1 before drinking |