Cold Brew Ratio Calculator
Get the perfect water-to-coffee ratio for smooth, balanced cold brew every single time.How Cold Brew Ratio Calculator Works
Cold brew is all about patience and the right ratios. Unlike hot coffee, cold brew uses room temperature water and time instead of heat to extract flavors from coffee grounds. The process takes 12-24 hours, but the result is a smooth, naturally sweet concentrate that's less acidic than traditional coffee.
This calculator helps you nail the perfect cold brew ratio based on your desired volume and brewing strength. You'll input how much finished cold brew you want and choose your preferred coffee-to-water ratio (typically ranging from 1:4 for a strong concentrate to 1:8 for a lighter brew). The calculator accounts for the fact that coffee grounds absorb about 20% of the water during brewing.
What makes cold brew special is the long extraction time at room temperature, which pulls out the sweet, chocolatey flavors while leaving behind much of the acidity and bitterness. The result is a concentrated brew that you can dilute with water, milk, or enjoy over ice for a refreshing coffee experience that's completely different from hot-brewed coffee.
Cold Brew Ratio Calculator Formula Breakdown
Formula
Water needed = Desired coffee volume ÷ 0.8
Coffee grounds needed = Water volume (in ml) ÷ Coffee ratio
Variables Explained
- Desired Coffee VolumeThe amount of finished cold brew you want to make, measured in ounces or milliliters. This is the volume you'll have after straining out the grounds and accounting for water absorption.
- UnitsChoose between ounces (oz) or milliliters (ml) for your measurements. The calculator will automatically convert and display results in your preferred unit system.
- Coffee RatioThe ratio of coffee to water, expressed as 1 gram of coffee to X milliliters of water. Common ratios range from 1:4 (very strong concentrate) to 1:8 (lighter brew). A 1:5 to 1:6 ratio is popular for most cold brew preferences.
Example Calculation
Given:
- Desired Coffee Volume: 20 oz
- Units: oz
- Coffee Ratio: 1:5.6
Calculation:
Water needed: 20 oz ÷ 0.8 = 25 oz
Convert to milliliters: 25 oz × 29.5735 = 739 ml
Coffee grounds needed: 739 ml ÷ 5.6 = 132 g
Result:
Use 25 oz of water and 132 g of coffee groundsExplanation
This example shows how to make 20 oz of cold brew concentrate at a 1:5.6 ratio, which produces a medium-strength brew perfect for drinking over ice or diluting with milk.
Tips for Using Cold Brew Ratio Calculator
- 💡Use a coarse grind similar to French press - this prevents over-extraction during the long steeping time and makes filtering easier.
- 💡Always brew in the refrigerator, not at room temperature, to prevent bacterial growth and ensure food safety during the long steeping process.
- 💡Start with a 1:6 ratio and adjust from there - if it's too strong, try 1:7 or 1:8, and if it's too weak, go with 1:5 or 1:4 for your next batch.
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