Coffee Ratio Calculator

Enter your coffee dose and brew ratio to get the exact amount of water — in grams and milliliters — for a balanced cup.

Quick Facts

Method
Golden ratio: water (g) = coffee (g) × ratio
1:15–1:17 for drip/pour-over, 1:2 espresso, 1:8 cold brew. Water is measured by weight; 1 g water ≈ 1 mL.

Your Results

Calculated
Water needed
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Grams of water for this dose
Same amount in mL
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Water volume (1 g ≈ 1 mL)
Total brew weight
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Coffee + water in the vessel
Strength band
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How the ratio reads

Ready

Enter your dose and ratio, then press Calculate.

How the coffee ratio calculator works

Brew ratio is the single biggest lever on how strong your coffee tastes. This calculator applies the standard relationship between coffee and water by weight: water (g) = coffee (g) × ratio, and its inverse, coffee (g) = water (g) ÷ ratio. A ratio written as 1:16 means one gram of coffee for every sixteen grams of water. Enter the amount you know — your coffee dose or a target amount of water — pick your ratio, and the tool returns the matching amount along with the total brew weight and a strength read.

The golden ratio

Most drip and pour-over methods target 1:15 to 1:17 (coffee:water by weight). The Specialty Coffee Association's "golden cup" standard centers near 55 grams of coffee per liter of water, which is about 1:18 by weight; many home baristas prefer the slightly stronger 1:16. Because water is close to 1 gram per milliliter, 480 grams of water is roughly 480 mL. Espresso runs much tighter at about 1:2 (a 20 g dose pulls a ~40 g shot), and cold brew concentrate is strong, around 1:8.

Common ratios at a glance

  • Espresso: ~1:2 (18–20 g in, 36–40 g out).
  • Moka pot / strong brew: ~1:10 to 1:12.
  • Pour-over / drip (balanced): 1:15 to 1:17 — the everyday sweet spot.
  • French press: ~1:15 (30 g coffee to 450 g water).
  • Cold brew concentrate: ~1:8, steeped 12–24 hours and later diluted to taste.

Ratio versus extraction

Ratio sets strength (how much coffee is dissolved into the cup). Grind size, water temperature, and contact time set extraction (which flavors come out). Fix ratio first with the scale, then dial in the rest:

  • Under-extracted (sour, thin): grind finer, extend contact time, or raise temperature.
  • Over-extracted (bitter, harsh): grind coarser, shorten time, or lower temperature.
  • Water temperature: 90–96 °C (195–205 °F) for most methods; espresso 90–94 °C.

Frequently Asked Questions

What is the golden coffee-to-water ratio?
For most drip and pour-over methods the golden ratio is about 1:15 to 1:17 by weight — one gram of coffee per 15 to 17 grams of water. The Specialty Coffee Association's mid-point is roughly 55 g of coffee per liter (about 1:18). Espresso is far tighter at about 1:2, and cold brew concentrate is stronger at about 1:8. Start at 1:16 and adjust to taste.
Should I measure water in grams or milliliters?
Brew ratios are defined by weight, so weigh both coffee and water in grams for the most repeatable results. Water's density is almost exactly 1 g/mL at brewing-relevant temperatures, so 1 gram of water is about 1 milliliter — 480 g ≈ 480 mL. A digital scale reading to 0.1 g beats measuring cups, which vary with how you scoop.
How much coffee for one cup?
A standard mug holds about 250 mL of water. At a 1:16 ratio that's 250 ÷ 16 ≈ 15.6 g of coffee. For a bolder cup drop to 1:15 (about 16.7 g); for a milder cup move to 1:17 (about 14.7 g). Remember the brewed volume in the cup is a little less than the water you pour, because the grounds retain roughly 2 g of water per gram of coffee.