Achieve the "Golden Cup" standard by calculating the perfect coffee-to-water ratio.
Mastering the Coffee-to-Water Ratio
The secret to a consistently delicious cup of coffee isn't just the quality of the beans—it is the math behind the extraction. The Coffee Brewing Ratio determines the strength and body of your drink. Whether you prefer a bold French Press or a delicate Pour-over, using a digital scale and this calculator ensures you never drink a "weak" cup again.
Recommended Ratios by Brewing Method
Method
Ratio (Coffee:Water)
Description
French Press
1:12 to 1:15
Strong, full-bodied, and textured.
Pour Over (Hario V60)
1:15 to 1:17
The "Golden Ratio" for clarity and balance.
Aeropress
1:10 to 1:16
Highly versatile depending on steep time.
Cold Brew
1:4 to 1:8
Concentrated; usually diluted before serving.
Calculation Examples
Example 1: The Standard Morning Mug
If you have a 300ml mug and want a standard 1:16 ratio, you divide 300 by 16.
Result: 18.75 grams of coffee.
Example 2: Using the Last of Your Beans
If you only have 20 grams of coffee left and want a 1:15 ratio, you multiply 20 by 15.
Result: 300ml of water.
Tips for Better Extraction
Use a Scale: Volumetric measurements (scoops/spoons) are inaccurate because coffee density varies by roast level.
Water Temp: Aim for 195°F to 205°F (90°C to 96°C) for optimal extraction.
Grind Size: Match your grind to your ratio. Finer grinds extract faster, while coarser grinds (like French Press) need more time.
function calculateCoffee() {
var water = parseFloat(document.getElementById('waterAmount').value);
var ratio = parseFloat(document.getElementById('brewRatio').value);
var resultDiv = document.getElementById('coffeeResult');
var resultText = document.getElementById('resultText');
if (isNaN(water) || isNaN(ratio) || water <= 0 || ratio <= 0) {
resultDiv.style.display = 'block';
resultText.innerHTML = 'Please enter valid numbers for Water and Ratio.';
return;
}
var coffeeNeeded = (water / ratio).toFixed(1);
resultDiv.style.display = 'block';
resultText.innerHTML = 'To brew with ' + water + 'ml of water at a 1:' + ratio + ' ratio, you need:' + coffeeNeeded + ' grams of coffee';
// Update the coffee input field for convenience
document.getElementById('coffeeGrams').value = coffeeNeeded;
}
function calculateWater() {
var coffee = parseFloat(document.getElementById('coffeeGrams').value);
var ratio = parseFloat(document.getElementById('brewRatio').value);
var resultDiv = document.getElementById('coffeeResult');
var resultText = document.getElementById('resultText');
if (isNaN(coffee) || isNaN(ratio) || coffee <= 0 || ratio <= 0) {
resultDiv.style.display = 'block';
resultText.innerHTML = 'Please enter valid numbers for Coffee and Ratio.';
return;
}
var waterNeeded = Math.round(coffee * ratio);
resultDiv.style.display = 'block';
resultText.innerHTML = 'With ' + coffee + 'g of coffee beans at a 1:' + ratio + ' ratio, you should use:' + waterNeeded + ' ml (grams) of water';
// Update the water input field for convenience
document.getElementById('waterAmount').value = waterNeeded;
}