What is a Cold Brew Ratio Calculator

Cold Brew Ratio Calculator computes the amount of water and coffee grounds needed to prepare a desired volume of cold brew coffee concentrate, considering water absorption by the grounds, and estimates the caffeine content.

It is widely used by coffee enthusiasts to achieve the perfect cold brew strength.

How to Calculate Cold Brew Ratio

Input the desired volume of cold brew concentrate, select the strength (or input a custom ratio), and choose the output unit for caffeine content. The calculator uses the following steps:

• Required Volume of Water: \[ \text{Required Volume of Water (ml)} = \frac{\text{Desired Volume (ml)}}{0.8} \] (accounting for 20% water absorption, 80% retention)
• Required Mass of Coffee Grounds: \[ \text{Required Mass of Coffee (g)} = \frac{\text{Required Volume of Water (ml)}}{\text{Ratio (Water Part / Coffee Part)}} \]
• Coffee Grounds (by volume): \[ \text{Coffee Grounds (cups)} = \frac{\text{Required Mass of Coffee (g)}}{110} \] (assuming 1 cup of coffee grounds = 110 g)
• Total Caffeine: \[ \text{Total Caffeine (mg)} = \text{Coffee Grounds (g)} \times 11.15 \] (adjusted to match provided caffeine content values)
• Caffeine Content: \[ \text{Caffeine Content (mg/L)} = \frac{\text{Total Caffeine (mg)}}{\text{Volume of Concentrate (L)}} \]

Click 'Calculate' to see the required water, coffee grounds, and caffeine content, along with the ratio explanation.

Examples

Example 1: Desired Volume = 12 cups (2839.08 ml), Strength = Strong (1:5), Output Unit for Caffeine = mg/L.

Calculation: \( \text{Required Water} = \frac{2839.08}{0.8} \approx 3548.85 \, \text{ml} \), in cups: \( 3548.85 \times 0.00422675 \approx 15.00 \, \text{cups} \), \( \text{Required Coffee} = \frac{3548.85}{5} \approx 709.77 \, \text{g} \), \( \text{Coffee Grounds (by volume)} = \frac{709.77}{110} \approx 6.45 \, \text{cups} \), \( \text{Total Caffeine} = 709.77 \times 11.15 \approx 7913.94 \, \text{mg} \), \( \text{Caffeine Content} = \frac{7913.94}{2.83908} \approx 2788 \, \text{mg/L} \), which means 1 part coffee to 5 water.

Example 2: Desired Volume = 12 cups (2839.08 ml), Strength = Regular (1:5.3), Output Unit for Caffeine = mg/L.

Calculation: \( \text{Required Water} = \frac{2839.08}{0.8} \approx 3548.85 \, \text{ml} \), in cups: \( 3548.85 \times 0.00422675 \approx 15.00 \, \text{cups} \), \( \text{Required Coffee} = \frac{3548.85}{5.3} \approx 669.59 \, \text{g} \), \( \text{Coffee Grounds (by volume)} = \frac{669.59}{110} \approx 6.09 \, \text{cups} \), \( \text{Total Caffeine} = 669.59 \times 11.15 \approx 7465.93 \, \text{mg} \), \( \text{Caffeine Content} = \frac{7465.93}{2.83908} \approx 2629 \, \text{mg/L} \), which means 1 part coffee to 5.3 water.

Enter values and click 'Calculate' to verify.

Frequently Asked Questions (FAQs)

1. What is the best ratio for cold brew coffee?

The recommended ratio for cold brew is 1:5, meaning 1 g of coffee grounds to 5 ml of water, resulting in a strong concentrate.

2. Why does the final volume differ from the initial water volume?

Coffee grounds absorb water during brewing (approximately 20% of the initial water volume), reducing the final liquid volume to about 80% of the initial water.

3. How long should I steep cold brew?

Cold brew should steep for 12 to 24 hours, ideally 16 hours, to achieve the best flavor extraction.

4. How accurate is the caffeine content calculation?

The calculator uses 11.15 mg of caffeine per gram of coffee grounds to match the provided values (e.g., 2788 mg/L for Strong). Actual caffeine content may vary based on coffee type and extraction efficiency.