How to Make Cold Brew Coffee at Home
Cold brew is an immersion method: ground coffee sits in cool water, then the grounds are filtered out. It is simple, forgiving, and easy to scale—but good results still depend on grind, ratio, time, cleanliness, and the coffee itself.
Cold-brew concentrate recipe
This recipe makes a concentrate to dilute before drinking.
- 200 grams whole coffee beans
- 1,000 grams filtered water
- A clean container with a lid
- A burr grinder
- A fine-mesh strainer plus paper or cloth filter
- Grind the coffee coarse, similar to coarse sea salt.
- Add grounds to the clean container.
- Pour in the water and stir gently until every particle is wet.
- Cover and steep about 8 to 12 hours at cool room temperature or in the refrigerator.
- Strain through a coarse filter, then filter again through paper or clean cloth for a clearer concentrate.
- Refrigerate promptly in a clean, covered container.
To serve, start with one part concentrate and one part water or milk over ice. Adjust from there.
Why use a coarse grind?
Cold brew keeps water and coffee together for hours. A fine grind extracts quickly, can create harshness, and is difficult to filter. Coarse particles slow the process and produce less sediment.
If the concentrate is weak, extend the steep slightly or use more coffee before making the grind dramatically finer.
Does it really need 24 hours?
Not necessarily. UC Davis Coffee Center research found that brew time was less important to sensory differences than roast level and brewing temperature in the tested full-immersion cold brews. Samples brewed for eight hours could produce similar sensory qualities to much longer brews.
Start tasting around eight hours. Filter when the concentrate has enough body and sweetness for you instead of treating 24 hours as a universal rule.
Choose the ratio for the drink you want
| Style | Starting ratio | How to serve |
|---|---|---|
| Concentrate | 1:4 to 1:5 | Dilute with water or milk |
| Ready to drink | About 1:10 to 1:12 | Serve directly over ice |
A scale makes scaling easy. At 1:5, use 100 grams of coffee with 500 grams of water or 300 grams with 1,500 grams of water.
Which roast works best?
There is no single cold-brew roast. A dark roast often creates cocoa, smoke, and a heavier profile. A lighter or naturally processed coffee can bring fruit and aroma.
- Sumatra Organic: rich and earthy for a deeper concentrate.
- Honduras Natural: strawberry, honeysuckle, citrus, and chocolate notes for a fruit-forward experiment.
- Double Dark Decaf: an evening or lower-caffeine cold-brew option.
How to fix common cold-brew problems
- Muddy: grind coarser and add a second paper filtration.
- Bitter or woody: shorten the steep, grind coarser, or try a lighter roast.
- Thin: increase the coffee dose or reduce dilution.
- Dull: use fresher beans, filtered water, and a clean container.
- Too intense: remember that concentrate is meant to be diluted.
Keep cold brew clean and cold
Cold brew does not receive the same sustained heat as hot coffee. Use clean equipment and potable water, cover the brew, filter with clean materials, and refrigerate the finished concentrate promptly. Discard it if it develops an unusual odor, visible growth, gas, or other signs of spoilage.
For a café-scale or packaged product, use a formal food-safety process rather than a home recipe.
One batch, three drinks
- Classic: concentrate, water, and ice.
- Creamy: concentrate, milk or oat milk, and a pinch of cinnamon.
- Cold-brew tonic: tonic water over ice with concentrate floated slowly on top.
Once the base recipe is consistent, change one variable at a time: origin, roast, ratio, or steep time. That is how a simple jar becomes a repeatable cold-brew system.
Hero photo: Nicola Barts on Pexels.
Sources: National Coffee Association cold-brew guide, UC Davis cold-brew timing research, and NCA cold-brew safety overview.