Coffee-to-Water Ratio Calculator
Calculate the perfect coffee-to-water ratio for any brew method and number of cups.
Coffee-to-water ratio is the most important variable in brewing great coffee. The Specialty Coffee Association (SCA) recommends a “golden ratio” of 1:15 to 1:18 (grams of coffee to grams of water).
Recommended ratios by brew method:
- Pour over (V60, Chemex) — 1:15 to 1:17. Lighter, cleaner extraction. Start with 1:16.
- French press — 1:14 to 1:16. Slightly stronger due to full immersion. Start with 1:15.
- Drip machine — 1:15 to 1:17. Match your machine basket size. Start with 1:16.
- AeroPress — 1:12 to 1:15. Concentrated brew, often diluted. Start with 1:13.
- Cold brew — 1:5 to 1:8. Very concentrated, dilute 1:1 with water or milk. Start with 1:7.
- Espresso — 1:1.5 to 1:2.5. Very different from filter coffee ratios.
- Moka pot — 1:10 to 1:12. Strong stovetop espresso-style.
Water temperature: 195–205°F (90–96°C) for hot brew methods. Boiling water (212°F / 100°C) over-extracts and creates bitterness. Water below 185°F (85°C) under-extracts and tastes sour.
Water quality: Use filtered water. Tap water with high chlorine or mineral content affects taste significantly. The SCA recommends water with 150 ppm total dissolved solids.
Cup sizes vary: A “cup” of coffee is typically 6 oz (177 ml) in the US, but a standard mug holds 8–12 oz (237–355 ml). This calculator uses actual fluid ounces so you get the right amount.
Grinding: Finer grinds extract faster and taste stronger at the same ratio. If your coffee tastes weak, try grinding finer before adding more coffee. If it tastes bitter, grind coarser.
Tip: Weigh your coffee with a kitchen scale for consistency. A tablespoon of coffee varies from 5–8 grams depending on grind size and bean density. Using weight eliminates this inconsistency.