Cold brew coffee is the easiest coffee you can make at home and the most economical. The process is almost entirely passive — you combine coffee and water, wait 12–24 hours, filter, and you have two weeks of cold brew in the fridge. This guide gives you the exact ratios, the most common mistakes, and two methods (mason jar and dedicated maker) that both work well.
The Ratio
There are two common cold brew targets: concentrate and ready-to-drink. Concentrate (1:4 coffee to water by weight) produces a strong base that you dilute 1:1 with water or milk when serving. It's more space-efficient in the fridge and lets you adjust strength to taste. Ready-to-drink (1:8 ratio) can be consumed straight without dilution. Most home cold brew recipes use the 1:4 concentrate approach.
For 32oz of concentrate: use 100g of coarse-ground coffee and 400g (approximately 400ml) of filtered cold water. This fills a standard 32oz mason jar and makes approximately 16–20 servings of diluted cold brew.
The Grind
Coarse grind — similar to French press or slightly coarser. On the Baratza Encore, setting 28–35. Coarse grinding is important for two reasons: it slows extraction so the long steep doesn't over-extract, and it makes filtering easier with less fine particle clogging. Pre-ground "cold brew" coffee sold in stores is usually pre-ground at the right coarseness and works well if you don't have a grinder.
Method 1: Mason Jar (No Equipment Needed)
Add coarse-ground coffee to a 32oz mason jar. Add filtered cold water. Stir gently to ensure all grounds are saturated. Place in the fridge (not on the counter — cold extraction in the fridge takes 18–24 hours; room temperature extraction takes 12–14 hours but produces slightly less clean results). After your target time, strain through a fine mesh strainer lined with a paper coffee filter or cheesecloth into a second container. Strain twice for the cleanest result. Store in the fridge for up to two weeks.
Method 2: OXO Cold Brew Maker (Recommended)
The OXO Good Grips Cold Brew Maker simplifies the process significantly. Its rainmaker lid distributes water evenly over the grounds for complete saturation. The perforated stainless steel filter eliminates the straining step — you simply flip the switch when ready and the concentrate drains directly into the included glass carafe. Cleanup is easier than the mason jar method and the results are consistently cleaner. The 32oz capacity matches the mason jar method.
Steep Time: The Variables
Fridge temperature: 18–24 hours. Room temperature (68–72°F): 12–14 hours. Longer steep times produce stronger, slightly more bitter results. If your cold brew tastes weak, steep longer next time or use more coffee. If it tastes bitter, steep shorter or use a coarser grind. The sweet spot for most medium-dark roasts at 1:4 ratio is 18 hours in the fridge.
Best Beans for Cold Brew
Medium-dark to dark roast Colombian, Brazilian, or Guatemalan beans produce the best cold brew. Their chocolate, caramel, and nutty notes are amplified by cold extraction. Light roast single origins often taste underdeveloped and flat in cold brew. Death Wish Coffee's dark roast grounds work particularly well — the bold, intense profile holds up beautifully when diluted with ice and milk.
Serving Ideas
Classic: over ice, diluted 1:1 with water. Café-style: over ice with oat milk or whole milk, no dilution needed. Sweetened: add simple syrup to taste before or after dilution. Nitrogen-style: pour from height into a glass half-filled with ice for a naturally foamy effect. Cold brew tonic: 2oz concentrate over ice, top with tonic water — unexpectedly delicious with fruit-forward light roast concentrate.