jar of coarse grounds and cold water goes into the fridge before bed. The next afternoon you strain it and pour it over ice. What you drink is smooth, sweet, and low in acid. That overnight wait is doing all the work.
Cold brew is immersion with no heat. Without hot water to drive things along, extraction crawls. Over many hours it pulls plenty of the sweet and soluble compounds but far less of the sharp acidic and bitter ones. The cup that comes out is mellow and rounded, which is the whole point of the method.
This guide gives you two ways to run it: a strong concentrate you dilute before serving, and a ready-to-drink batch you pour straight. Both use the same coarse grind and the same long steep. Pick one and start a batch tonight.
Cold brew is not iced coffee
These two get mixed up constantly, and they are not the same drink. Iced coffee is brewed hot, the normal way, and then cooled down over ice. Cold brew never meets heat at all. It steeps in cold or room-temperature water from start to finish.
That difference changes the cup. Hot water extracts acids and bitter compounds quickly, so even a chilled hot brew keeps that brighter, sharper character. The slow cold steep leaves most of those compounds behind, which is why cold brew tastes smooth, sweet, and noticeably low in acid. If you want a bright, lively iced cup, brew hot and chill it. If you want mellow and round, cold brew it.
| Property | Cold brew | Iced coffee |
|---|---|---|
| Water temperature | Cold or room temp, never heated | Brewed hot, then chilled |
| Brew time | 12 to 18 hours | Minutes |
| Grind | Very coarse | Normal for the hot method used |
| Acidity | Low, mellow | Brighter, sharper |
| Typical character | Smooth, sweet, rounded | Lively, more aromatic |
What you need and how to set it up
You need a jar or pitcher with a lid, a scale, coarse-ground coffee, and a way to strain at the end. A paper filter or a fine cloth both work for straining. No kettle, no thermometer, no timer beyond a rough sense of when the next day arrives.
Grind very coarse, coarser than you would for a French press. The long steep is unforgiving of fine grounds: they over-extract and turn the cup muddy and harsh. Fine particles also clog the filter when you try to strain. Big, even particles steep cleanly and pour clear.
Decide which version you want before you weigh anything. Concentrate uses roughly 1 part coffee to 8 parts water, steeps strong, then gets diluted at serving time. Ready-to-drink uses roughly 1 part coffee to 15 parts water and is poured as is. Concentrate is the more flexible choice: you can dilute with water, milk, or more ice to taste. It also keeps longer in the fridge.
The brew, step by step
A worked concentrate batch: 100 g of very coarse coffee and 800 g of cold water, which is the 1:8 ratio. For ready-to-drink, swap to 100 g coffee and 1500 g water and skip the dilution at the end. Everything else is identical.
- CombineAdd 100 g of very coarse grounds to the jar, then pour in 800 g of cold or room-temperature water.800 g
- Wet every groundStir gently until all the grounds are saturated and none float dry on top. Dry pockets steep unevenly.
- Cover and steepPut the lid on and leave it at room temperature for 12 to 18 hours. In the fridge the same brew can go up to about 24 hours, since cold slows extraction further.900:00
- StrainPour the brew through a paper filter or a fine cloth into a clean container. For a cleaner cup, strain a second time. Discard the grounds.
- DiluteFor concentrate, mix roughly 1 part concentrate to 1 part water or milk, then adjust to taste. Skip this step for a ready-to-drink batch.
- Serve over icePour over ice and serve. Store the rest in the fridge.
Storing and adjusting
Cold brew keeps well in a sealed container in the fridge for about a week. Concentrate holds a little longer because there is less water for flavor to fade into, which is a practical reason to brew strong and dilute per glass. Taste it as the days pass and you will notice it slowly softening.
If the cup tastes weak or watery, you over-diluted or steeped too short: cut back the dilution water, or push the steep toward 18 hours next time. If it tastes harsh, drying, or muddy, the grind was too fine or the steep ran too long: grind coarser and pull the batch at 12 to 14 hours. Change one thing per batch so you can read what it did.
Common questions
- Is cold brew the same as iced coffee?
- No. Iced coffee is brewed hot and then cooled over ice, so it keeps a brighter, sharper, more acidic character. Cold brew steeps in cold or room-temperature water for many hours and never meets heat, which is why it tastes smooth, sweet, and low in acid. They are two different drinks made two different ways.
- What grind should I use for cold brew?
- Very coarse, coarser than a French press grind. Fine grounds over-extract during the long steep and turn the cup muddy and harsh. They also clog whatever you strain through. Large, even particles steep cleanly over 12 to 18 hours and pour clear.
- How long does cold brew keep?
- About a week in a sealed container in the fridge. A concentrate keeps a little longer than a ready-to-drink batch because there is less water diluting the flavor. The taste softens slowly over those days rather than spoiling suddenly, so trust your palate near the end.