How to Make Cold Brew Coffee at Home: A Simple Guide

Quick answer

To make cold brew at home, combine coarsely ground coffee with cold water at a 1:8 ratio by weight, stir gently, and steep in the refrigerator for 12–18 hours. Then strain through a fine-mesh sieve or paper filter. This method gives you a smooth concentrate you can dilute to taste, and it works with almost any coffee you already enjoy.

Cold brew is one of the most forgiving ways to make coffee at home. It does not require a precise pour or a temperature-controlled kettle, and the slow steep smooths out bitterness while keeping sweetness intact. The tradeoff is time: you need to plan ahead, usually the night before.

This guide walks through a reliable cold brew coffee recipe, explains how to adjust the cold brew ratio for your taste, and covers the gear that actually makes a difference. You can use the same method whether you prefer a bright Ethiopian coffee or a deeper, chocolatey blend.

What you need before you start

You do not need a dedicated cold brew maker. A large jar, a bowl, or a French press works fine. What matters more is the grind and the ratio. Aim for a coarse grind, similar to raw sugar or sea salt. If you grind too fine, the brew will turn muddy and bitter, and straining becomes a chore.

For filtering, a fine-mesh sieve lined with a paper filter catches the silt that a metal filter alone misses. Chemex Coffee Filters are thicker than most cone filters, which helps trap fine grounds and oils while letting the coffee drain at a steady pace. If you already own one, it is a practical option for the straining step.

• Use a scale if you have one. Volume scoops vary too much for a repeatable cold brew ratio.
• Start with filtered water. Tap water with heavy chlorine can flatten the coffee's sweetness.

Choosing coffee and grind size

Any freshly roasted coffee can become cold brew, but the roast level changes the result. Medium and dark roasts tend to produce deeper chocolate and caramel notes, while light roasts keep more fruit and floral character. If you want a concentrate that tastes good with milk or oat milk, a blend with natural sweetness is a safe starting point.

Grind coarse and keep it consistent. If your grinder produces a lot of fines, sift them out or expect a slower strain and a heavier body. A burr grinder gives you more control here than a blade grinder, but you can still make good cold brew with pre-ground coffee if you buy it coarse.

• Grind just before brewing if you can. Pre-ground coffee loses aromatics faster.
• If the brewed concentrate tastes bitter, your grind was likely too fine or your steep went too long.

The cold brew ratio and steeping time

A 1:8 coffee-to-water ratio by weight makes a strong concentrate. For example, 100 grams of coffee to 800 grams of water. You can dilute that concentrate with water, milk, or ice at serving time. If you prefer to drink it straight, use a 1:12 to 1:15 ratio instead. Those are starting points, not rules.

Steep in the refrigerator for 12 to 18 hours. Room-temperature steeping works too and finishes faster, around 8 to 12 hours, but it can pull out more bitterness and is less forgiving if you forget it. Refrigerator steeping is slower and cleaner-tasting. Write down your ratio and time so you can adjust the next batch.

• Stir once at the beginning and once at the halfway point. Do not agitate it constantly.
• If the result tastes weak, increase coffee by 10–15% next time rather than steeping much longer.

Straining and storing your cold brew

Pour the steeped mixture through a fine-mesh sieve to catch the bulk of the grounds, then strain again through a paper filter for a cleaner cup. Avoid squeezing the grounds; pressing them releases fine particles and bitterness. Let gravity do the work, even if it takes a few minutes.

Store the finished concentrate in a sealed jar in the refrigerator. It keeps well for about a week, though flavor peaks in the first three or four days. Label the jar with the date and ratio if you plan to make cold brew a regular habit.

• A second strain through paper takes longer but noticeably improves clarity.
• Serve over ice and dilute to taste. Cold brew concentrate is strong by design.

Cold brew step by step

1. Weigh and grind your coffee: For a 1:8 concentrate, weigh 100 g of coffee and grind it coarse, like raw sugar. If you do not have a scale, use 1 cup of coarse grounds to 4 cups of water as a rough starting point. Checkpoint: the grind should feel like coarse sand, not powder. Adjust your grinder one notch coarser if it looks fine.
2. Combine coffee and cold water: Add the grounds to a jar or pitcher, pour in 800 g of cold filtered water, and stir gently until all the grounds are saturated. Cover the container. Common mistake: leaving dry clumps floating on top. Stir again after five minutes if needed.
3. Steep in the refrigerator: Refrigerate for 12 to 18 hours. If you prefer room-temperature steeping, aim for 8 to 12 hours and taste at the 8-hour mark. Checkpoint: taste a small spoonful at 12 hours. If it tastes balanced, strain now. If it is weak, give it a few more hours.
4. Strain twice: Pour through a fine-mesh sieve, then strain the liquid again through a paper filter such as a Chemex Coffee Filter. Do not press or squeeze the grounds. Common mistake: rushing the second strain. Let it drip; forcing it adds silt and bitterness.
5. Store and serve: Keep the concentrate in a sealed jar in the refrigerator for up to a week. Dilute with water, milk, or ice at a 1:1 or 1:2 ratio, depending on how strong you like it. Next step: note your ratio and steep time. Adjust coffee by 10% up or down next batch to dial in your preference.

Gear that helps

• Chemex Coffee Filters: These cone-shaped filters use 20–30% thicker paper than the competition, which results in more uniform coffee extraction and helps catch bitter elements, oils, and the finest grounds. For cold brew, thicker paper means a cleaner concentrate with less sediment and a smoother texture, especially if your grind produced some fines.
• Acaia Lunar Scale: The Acaia Lunar scale is designed for coffee enthusiasts that mind weight, time, and flow rate as you brew coffee, with a compact size that fits into the drip tray of an espresso machine. A scale makes your cold brew ratio repeatable. Weighing coffee and water is the single easiest way to fix a batch that tastes too weak or too strong.
• Ethiopia Biftu Gudina: Grown at 2,100 meters in Ethiopia’s Limu region, this washed coffee highlights bright citrus and concentrated sweetness, and each coffee is roasted to order. Washed Ethiopian coffees make a lively, fruit-forward cold brew. If you usually drink dark roast cold brew, this is a good way to try something brighter.

Cold brew rewards a little planning and almost no technique. Pick a coarse grind, a ratio you can remember, and a steeping time that fits your schedule, then adjust from there. Once you have a batch you like, the recipe becomes as routine as making toast.