Cold Brew Coffee Ratio Guide: The Perfect Recipe and Steep Time
Cold brew is forgiving, but the ratio, grind and time decide whether you get smooth chocolatey coffee or a flat, muddy one. Here is the exact formula, why it works and how to adjust it.
Quick answer: use a 1:8 coffee-to-water ratio by weight (100 g coarse coffee to 800 g cold water), steep for 16 hours at room temperature, filter, then dilute the concentrate 1:1 with water or milk over ice.
What Is the Best Cold Brew Coffee Ratio?
Cold water extracts flavor far more slowly than hot water, so cold brew needs more coffee than drip. Most people make a concentrate and dilute it, because it stores better and lets every drinker set their own strength.
| Style | Coffee : Water | Example | Serve |
|---|---|---|---|
| Strong concentrate | 1:5 | 100 g : 500 ml | Dilute 1:2 |
| Standard concentrate | 1:8 | 100 g : 800 ml | Dilute 1:1 |
| Ready to drink | 1:15 | 60 g : 900 ml | Straight over ice |
| Light and tea-like | 1:17 | 50 g : 850 ml | Straight over ice |
No scale? One cup of coarse coffee weighs roughly 85 g, so 1 cup of grounds to 3 cups of water gives a concentrate close to 1:8.
Cold Brew Ratio Calculator
How to Make Cold Brew Coffee: Step by Step
This recipe makes about 1.4 liters of drinkable cold brew, enough for 6 large glasses.
- Grind 100 g of coffee very coarse. It should look like raw sugar or coarse sea salt.
- Combine with 800 ml of cold filtered water in a jar or pitcher. Stir gently until no dry clumps remain.
- Cover and steep 14–18 hours at room temperature, or 18–24 hours in the fridge.
- Filter twice. First through a fine mesh sieve, then through a paper filter or cloth for a clean cup.
- Dilute 1:1 with water or milk, pour over ice and taste. Adjust with more concentrate if needed.
Grind Size and Best Beans for Cold Brew
Grind coarse
A coarse grind gives an even, slow extraction and is easy to filter. Fine grounds over-extract, release bitter compounds and clog filters. If your grinder has numbers, use the coarsest French press setting or one step coarser.
Choose medium to dark roasts
Cold brew mutes acidity and brings out body, so beans with chocolate, caramel and nut notes shine. Brazilian, Colombian and Guatemalan coffees are reliable picks. Bright, fruity light roasts can taste flat when cold brewed.
Cold Brew Steep Time and Temperature
| Where | Steep time | Result |
|---|---|---|
| Room temp (20–22 °C) | 12 h | Light, slightly thin |
| Room temp (20–22 °C) | 16 h | Balanced, sweet (best) |
| Fridge (4 °C) | 20–24 h | Very smooth, mellow |
| Any | 30 h + | Woody, bitter, papery |
Warmer water extracts faster. In a hot kitchen above 26 °C, cut the time to 12–14 hours or move the jar to the fridge.
Common Cold Brew Mistakes
- Using a fine grind. The result is muddy, bitter and full of sediment.
- Steeping too long. More time does not mean more flavor after about 20 hours.
- Squeezing the filter. Pressing the grounds pushes bitter fines into the coffee.
- Using tap water with chlorine. Filtered water gives a cleaner, sweeter cup.
- Forgetting to dilute. Straight 1:8 concentrate is harsh and very strong.
Cold Brew FAQ
What is the best cold brew coffee ratio?
For a concentrate, use 1:8 coffee to water by weight (100 g coffee to 800 g water) and dilute 1:1. For ready-to-drink cold brew, use 1:15 to 1:17.
How long should cold brew steep?
Steep 14 to 18 hours at room temperature or 18 to 24 hours in the refrigerator. Past 24 hours the coffee turns woody and bitter.
How long does cold brew last in the fridge?
Undiluted concentrate keeps 10 to 14 days in a sealed container in the fridge. Diluted cold brew is best within 2 to 3 days.
Is cold brew stronger than hot coffee?
Concentrate is stronger, but once diluted 1:1 a cup of cold brew has roughly the same caffeine as drip coffee, about 100 to 150 mg per 240 ml.
Can I use regular ground coffee for cold brew?
Yes, but pre-ground coffee is usually too fine. It will taste muddier and be harder to filter. Shorten the steep to about 12 hours and filter twice.