Cooking & Food
Coffee Ratio Calculator - Brew the Perfect Cup
Calculate the ideal coffee-to-water ratio for pour-over, French press, espresso, and other brew methods. Works in grams or tablespoons.
The golden ratio
The Specialty Coffee Association (SCA) recommends a brew ratio of 1:15 to 1:18 (coffee:water by weight). The most common starting point is 1:16 - 1g of coffee for every 16g (ml) of water.
Brew method ratios
| Method | Ratio (coffee:water) | Grind size |
|---|---|---|
| Espresso | 1:2 (in:out by weight) | Very fine |
| AeroPress | 1:6 – 1:15 | Fine to medium |
| Pour-over (V60, Chemex) | 1:15 – 1:17 | Medium |
| French press | 1:12 – 1:15 | Coarse |
| Cold brew | 1:4 – 1:8 | Coarse |
| Moka pot | 1:7 | Fine (coarser than espresso) |
Extraction and taste
Under-extracted (too little time or water): sour, salty, hollow flavor. Over-extracted (too much time or fine grind): bitter, harsh, dry finish. Adjust your grind size first; adjust your ratio second.
Water quality matters
Water is 98–99% of your brewed coffee, so its mineral content directly affects extraction. The Specialty Coffee Association recommends water with a Total Dissolved Solids (TDS) of approximately 150 ppm and hardness between 50–175 ppm. Very hard water (high magnesium and calcium) causes over-extraction and bitter flavors; very soft water (near-zero TDS, such as distilled water) under-extracts and tastes flat. Filtered tap water is usually the easiest starting point.
Bloom / pre-infusion
Fresh coffee releases CO₂ gas (off-gassing) that was absorbed during roasting. When you first add hot water to ground coffee, this CO₂ escapes rapidly, creating a bloom or "crust". If you don't allow the gas to escape first, it can interfere with even water distribution and extraction. The standard bloom technique is to add twice the weight of water as coffee (e.g., 30 g water for 15 g grounds) and wait 30–45 seconds before pouring the rest. This is especially important for pour-over methods. Coffee roasted within the past 1–2 weeks blooms most vigorously.
Freshness guide
- Buy within the roast date: look for a roast date on the bag (not a "best by" date). Aim to buy coffee roasted within the last 4 weeks and consume it within 2–4 weeks of the roast date for optimal flavor.
- Grind immediately before brewing: pre-ground coffee goes stale within hours of grinding due to the massive increase in surface area exposed to oxygen. A burr grinder produces more consistent particle sizes than a blade grinder and is strongly preferred for pour-over and espresso.
- Storage: store beans in an airtight, opaque container at room temperature. Refrigerating coffee is generally not recommended (moisture and odor absorption). Freezing works for long-term storage of unopened, vacuum-sealed bags only.