COLD BREWCold Brew Concentrate
The quick answer
Use a 1:4 coffee-to-water ratio by weight (100g coffee to 400g water) to make concentrate. Steep coarse-ground coffee 18-24 hours in the fridge, then strain. Dilute 1:1 with cold water or milk before drinking. The result is a smooth, low-acid coffee base that lasts two weeks refrigerated.
Cold brew concentrate gives you cafe-quality iced coffee in seconds every morning, and one batch lasts all week in the fridge.
Grind size is the first lever to get right. Use a coarse grind, similar to raw sugar in texture. Fine grounds over-extract during the long steep and leave a bitter, murky brew. A coarse grind also filters more cleanly through paper or cheesecloth.
The 1:4 ratio by weight is the sweet spot for concentrate. That is 100 grams of coffee to 400 grams of water. Steep at room temperature for 12-16 hours or in the fridge for 18-24 hours. Cold steeping is slower but produces a cleaner, slightly sweeter cup.
Concentrate vs. ready-to-drink cold brew is a simple distinction: concentrate uses less water and must be diluted before drinking, while ready-to-drink brews at 1:8 and pours straight over ice. Concentrate is more efficient because one batch yields twice as many servings.
Filtering matters more than most beginners expect. A paper coffee filter removes fine sediment and most oils, giving you a clean, bright cup. A metal filter or cheesecloth keeps more oils in and produces a heavier body. Both work - it comes down to personal preference.
Dial it in before you make it
Get the coffee-to-water ratio right for concentrate or ready-to-drink.
| Ingredient | Amount |
|---|---|
| Coffee grounds | 189.6 g |
| Coffee grounds (tablespoons) | 35.8 tbsp |
| Water | 948 g |
| Water (cups) | 4.00 cups |
Serving tip
Dilute 1:1 with water or milk to serve — this batch makes ~8.0 cups of ready-to-drink cold brew.
1 tbsp ground coffee ≈ 5.3 g · 1 cup water = 237 g · 1 fl oz water = 29.57 g. Steep 12–24 h in the refrigerator.
Make it
Makes 8 drinks
Ingredients
Steps
We tested this ratio across three roast levels and two grind sizes at Home Cafe Lab. The 1:4 cold-steep method consistently produced the smoothest, most versatile concentrate - equally good straight over ice, with oat milk, or as the base for a sweet cream cold brew.
Pro tips
- Use filtered water - tap minerals can taste sharp in cold brew.
- Do not squeeze or press the grounds when filtering; pressing pushes bitter compounds through.
- Label the jar with the brew date so you always know when to use it by.
- For a less intense result, dilute 1:2 (concentrate to water) instead of 1:1.
- Room-temperature steeping (12-16 hours) is faster; fridge steeping (18-24 hours) gives a cleaner cup.
Frequently asked questions
What is the best coffee-to-water ratio for cold brew concentrate?
A 1:4 ratio by weight is the standard for concentrate. Use 100g coffee to 400g water, then dilute the finished concentrate 1:1 before drinking. This gives you a smooth, strong base without bitterness.
Can I use pre-ground coffee for cold brew concentrate?
Yes, but only if it is labeled coarse grind. Most pre-ground coffee is too fine and will over-extract during the long steep, making the brew bitter and difficult to filter cleanly.
How long does cold brew concentrate last in the fridge?
Up to 2 weeks in a sealed jar. Once diluted, drink within 3-4 days for best flavor. Always store concentrate separate from milk or water additions.
Should I steep cold brew in the fridge or at room temperature?
Either works. Room temperature steeping takes 12-16 hours. The fridge takes 18-24 hours but produces a cleaner, slightly sweeter cup with less astringency. Both are valid approaches.
Why is my cold brew concentrate bitter?
The most common causes are grinding too fine, steeping beyond 24 hours, or pressing the grounds during filtering. Try a coarser grind and a gentle pour-through filter next time.
