Getting the coffee-to-water ratio right is the single most reliable way to improve your cup. Too much coffee and it tastes bitter and harsh. Too little and it tastes weak and watery. Use the calculator below to find the right amount for your brew method and serving size.
Standard Ratios by Brew Method
| Brew Method | Ratio (Coffee:Water) | Grams per 300ml | Notes |
|---|---|---|---|
| Drip coffee | 1:15 to 1:17 | 18–20g | Standard starting point |
| Pour over | 1:15 to 1:16 | 19–20g | Adjust to taste |
| French press | 1:12 to 1:15 | 20–25g | Coarser grind, slightly stronger |
| AeroPress | 1:10 to 1:15 | 20–30g | Varies widely by recipe |
| Espresso | 1:2 to 1:2.5 | 18–20g in, 36–40g out | By weight, not volume |
| Cold brew concentrate | 1:4 to 1:5 | 60–75g per 300ml water | Dilute before drinking |
| Cold brew ready-to-drink | 1:8 | 37g per 300ml water | No dilution needed |
How to Use the Ratio
The ratio is expressed as coffee:water by weight. A 1:15 ratio means 1 gram of coffee for every 15 grams (or milliliters) of water.
Example: If you want 400ml of drip coffee at a 1:15 ratio: 400 ÷ 15 = 26.7 grams of coffee
Example: If you have 20 grams of coffee and want to know how much water to use at 1:16: 20 × 16 = 320ml of water
Unit Conversions
| Unit | Equivalent |
|---|---|
| 1 tablespoon of coffee | ~5–7 grams (varies by grind) |
| 1 cup of water | 240ml / 8 oz |
| 1 oz of water | ~28ml |
| 1 fluid oz | 29.6ml |
Note: Volume measurements for coffee (tablespoons, scoops) are less accurate than weight because grind size affects density. A kitchen scale is the most reliable tool for consistent results.
Adjusting to Taste
Start with the middle of the recommended range and adjust from there:
- Coffee tastes too strong or bitter → Use less coffee (move toward the higher water ratio, e.g., 1:17)
- Coffee tastes too weak or watery → Use more coffee (move toward the lower water ratio, e.g., 1:14)
- Coffee tastes sour → The issue is likely grind or temperature, not ratio. See Why Does My Coffee Taste Bitter?