How to Use This Coffee Ratio Calculator
This coffee to water ratio calculator gives you a tested starting point for any brewing method. Choose your method, set how much coffee you want to make, and pick your preferred strength. The calculator instantly shows you the exact grams of coffee and water, the right grind size, water temperature, and a step-by-step brewing guide.
A note on measuring: for the most consistent results, weigh your coffee and water with a kitchen scale rather than using scoops or cups. A tablespoon of coffee can weigh anywhere from 4 to 7 grams depending on the bean and grind, which makes volume measurements unreliable. The gram values shown here are the accurate target.
The Golden Ratio Explained
The Specialty Coffee Association established what is widely called the "golden ratio" - 1 gram of coffee for every 16 to 18 grams of water, written as 1:16 to 1:18. This produces a balanced cup that is neither too weak nor too bitter, and it works as a reliable default for filter and pour over methods.
However, the golden ratio is a starting point, not a universal rule. Different brewing methods extract coffee at different rates, so each one has its own ideal ratio. Immersion methods like French press benefit from a slightly stronger ratio because steeping is less efficient at extraction. Pressure methods like espresso use far less water. Cold brew uses the least water of all because cold extraction is slow and concentrated.
Coffee-to-Water Ratio Chart by Method
| Method | Ratio (balanced) | Grind | Temp | Brew time |
|---|---|---|---|---|
| Pour Over (V60, Kalita) | 1:16 | Medium | 94°C / 201°F | 2:30 - 3:30 |
| French Press | 1:15 | Coarse | 94°C / 201°F | 4:00 |
| AeroPress | 1:14 | Medium-fine | 85°C / 185°F | 1:30 - 2:00 |
| Chemex | 1:16 | Medium-coarse | 94°C / 201°F | 4:00 - 4:30 |
| Drip Machine | 1:16 | Medium | 92-96°C / 197-205°F | 5:00 - 6:00 |
| Moka Pot | 1:11 | Fine | Stovetop | 4:00 - 5:00 |
| Cold Brew (concentrate) | 1:8 | Coarse | Cold / room temp | 12 - 18 hrs |
| Siphon | 1:15 | Medium | 92°C / 198°F | 1:30 steep |
Choosing Your Strength
The strength setting adjusts the ratio within each method's sensible range:
- Mild uses more water per gram of coffee for a lighter, more tea-like cup that highlights delicate flavours.
- Balanced follows the SCA Golden Cup Standard for that method - the recommended default for most people.
- Strong uses less water per gram for a bolder, fuller cup with more body.
- Robust is the most concentrated setting, producing an intense cup. Best for those who take milk or who prefer a powerful flavour.
Remember that strength refers to flavour intensity, not caffeine content. Caffeine depends more on the bean type, roast level, and total brew method than on the ratio alone.
Water Temperature Matters
The SCA recommends a brewing temperature between 90.5 and 96 degrees Celsius (195 to 205 Fahrenheit) for hot methods. Water that is too hot over-extracts and produces bitterness; water that is too cool under-extracts and produces sourness. If you do not have a temperature-controlled kettle, bring water to a boil and let it rest for 30 to 60 seconds before pouring. AeroPress is the exception - many recipes use cooler water around 85 degrees Celsius for a smoother cup.