Coffee Ratio Calculator
About This Tool
This coffee ratio calculator computes water-to-coffee ratios for 11 brewing methods using data from the SCA Gold Cup Standard (55 g/L), Methodical Coffee, Honest Coffee Guide, Mt. Whitney Coffee Roasters, CoffeeGeek, Seven Coffee Roasters, KS Coffee, and James Hoffmann. Includes bloom water calculation for pour-over methods, an 11-level grind scale, brew temperature, and brew time. All processing runs locally in your browser.
How to Use
- Select a brewing method from the 11 available options (pour over, French press, drip, espresso, cold brew, AeroPress, Moka pot, Chemex, Turkish, siphon).
- Choose a strength preset (light, medium, strong, extra strong), then select an input mode (by water, by coffee, or by cups) and enter your amount.
- View your results: coffee amount (g / tbsp / scoops), water amount (ml / fl oz), ratio, bloom water, grind size, brew temperature, and brew time.
Methodology
Coffee-to-water ratios are based on the Specialty Coffee Association (SCA) Golden Cup standard, which recommends 55 g of coffee per liter of water (approximately 1:18 ratio) as the baseline for optimal extraction. The calculator adjusts ratios by brewing method: pour-over uses 1:15–1:17 for a cleaner cup, French press uses 1:15 for full-body immersion, espresso uses 1:2 by weight for concentrated extraction, cold brew uses 1:8 for extended steeping, and AeroPress uses 1:12–1:16 for its hybrid pressure method. Water volume is computed from the desired number of servings multiplied by a standard serving size, then divided by the ratio to determine the coffee dose. All method-specific ratios are sourced from SCA standards and professional barista guidelines.
Understanding Your Results
The water-to-coffee ratio is the single most important variable controlling your brew strength. A lower ratio (e.g., 1:12) means more coffee per unit of water, producing a stronger, more concentrated brew. A higher ratio (e.g., 1:18) produces a lighter, more delicate cup. Ratio Ranges by Strength: • 1:10–1:13: Strong/concentrated — typical for espresso-style drinks and Turkish coffee • 1:14–1:16: Medium-strong — ideal for pour-over and AeroPress, most people's preference • 1:16–1:18: SCA Gold Cup range — the standard for drip/batch brewing (55 g/L) • 1:18–1:20: Light — suited for those who prefer a milder, tea-like brew Grind Size (0–10 Scale): The grind scale ranges from 0 (Turkish extra-fine, like powdered sugar) to 10 (cold brew extra-coarse, like sea salt). Finer grinds extract faster and suit shorter brew times; coarser grinds extract slower and suit immersion methods. Using the wrong grind size is the most common cause of bitter (too fine) or sour (too coarse) coffee. Bloom Water: For pour-over methods, the bloom step uses twice the weight of the coffee grounds in water (e.g., 30 ml for 15 g coffee). This initial pour releases CO₂ trapped in freshly roasted beans, allowing more even extraction during the main pour. Skip the bloom only if your beans are more than 3–4 weeks past roast date. Brew Temperature: The recommended 195–205°F (90–96°C) range maximizes extraction of desirable flavor compounds while minimizing bitterness. Water below 190°F under-extracts (sour, weak); water above 205°F over-extracts (bitter, harsh).
Practical Examples
Example 1 — Pour-Over Single Cup (Medium Strength) Settings: Pour over method, standard 8 oz cup (237 ml), medium strength Results: 15g coffee (about 3 tablespoons), 237 ml water, ratio 1:16 Grind: Medium-fine (level 4), like table salt Bloom: 30 ml water, wait 30–45 seconds Brew temperature: 200°F (93°C), total brew time ~3 minutes Example 2 — French Press for Two (Strong) Settings: French press method, 2 cups (474 ml), strong strength Results: 32g coffee (about 6.5 tablespoons), 474 ml water, ratio 1:15 Grind: Coarse (level 7), like raw sugar crystals No bloom needed — immersion method Brew temperature: 200°F (93°C), steep 4 minutes, then press slowly Tip: After pressing, pour immediately to stop extraction — leaving coffee in the press continues brewing
Brewing Tips & Common Mistakes
• Invest in a kitchen scale that reads to 0.1 grams. Coffee-to-water ratio precision matters more than any other variable — a 2-gram difference in coffee can noticeably change the cup. Scoops and tablespoons are rough approximations at best. • Grind immediately before brewing. Ground coffee begins losing aromatic compounds within 15 minutes of grinding. If you notice your coffee tasting flat or stale, grinding fresh is the single biggest improvement you can make. • Use filtered water, not distilled. The SCA recommends water with 75–250 ppm total dissolved solids. Distilled water lacks the minerals needed for proper extraction and produces flat-tasting coffee. Hard water above 250 ppm causes over-extraction and chalky bitterness. • For cold brew, always start with the concentrate ratio (1:5 to 1:8) and dilute to taste. Cold water extracts differently than hot — it pulls fewer bitter compounds but also fewer bright acids, resulting in a naturally smooth, sweet concentrate that's meant to be diluted 1:1 with water or milk. • Adjust one variable at a time. If your coffee tastes bitter, try a coarser grind before changing the ratio. If it tastes sour or weak, try a finer grind first. Changing ratio and grind simultaneously makes it impossible to identify what fixed (or worsened) the result.
Sources
All calculations are performed locally in your browser. No data is sent to any server.