Cold brew ratio and how to make it at home

Cold brew is ground coffee steeped in cold or room-temperature water for many hours, then strained. Without heat, extraction is slower and gentler, which is why cold brew tends to taste smooth, rounded and low in bitterness. It's perfect for batch prep: make one jar on Sunday and you've got iced coffee all week.

The cold brew ratio, simply

Ratios are written as coffee : water by weight. There are two families:

• Concentrate, 1:4 to 1:6. Strong, meant to be diluted with water or milk before drinking. 1:5 is a great default (200 g coffee per litre of water).
• Ready-to-drink, 1:8 to 1:12. Brewed at drinking strength. 1:8 is good over lots of ice; 1:10 is lighter.

Different jar size? The cold brew calculator works it out for any batch and tells you when it'll be ready.

No scale? Cold brew ratio in cups

Coarse ground coffee weighs roughly 80 to 90 g per cup when loosely scooped, so volume ratios are approximate:

• 1 cup coarse grounds + 2 cups water ≈ 1:5 to 1:6, a concentrate.
• 1 cup coarse grounds + 4 cups water ≈ 1:11, a ready-to-drink strength.

Measure the same way every time and adjust to taste. It's cold brew: small differences are very forgiving.

How to make cold brew, step by step

1. Grind coarse. Aim for coarse, like rough sea salt. Fine grounds make cloudy, muddy cold brew that's hard to strain. See the grind size chart.
2. Combine. Add the coffee to a large jar or pitcher, pour in cold or room-temperature filtered water and stir gently until every ground is wet.
3. Steep. Cover and steep 12 to 18 hours at room temperature or 16 to 24 hours in the fridge.
4. Strain twice. Pour through a fine sieve to catch the grounds, then through a paper coffee filter or a cloth for a clean, silky result. Don't squeeze the grounds; it pushes bitter fines through.
5. Store. Bottle it in a clean, sealed jar and refrigerate.
6. Serve. For concentrate, mix about 1:1 with water or milk over ice. For ready-to-drink, pour over ice as is.

Which beans make the best cold brew?

Medium and medium-dark roasts give the classic cold brew flavors: chocolate, caramel, nuts. Light roasts make a brighter, fruitier cold brew that some people love and others find thin. Look for beans described with words like cocoa, brown sugar or toasted nuts if you want the traditional taste. Freshness still matters, but slightly older beans (a month or so after roasting) are more forgiving in cold brew than in pour-over.

Water matters here too

Cold brew is mostly water, so any off flavors in your tap water will show up in the glass. If your water tastes of chlorine, use filtered water or let a jug stand uncovered in the fridge overnight before brewing. Avoid distilled water, which makes flat, lifeless coffee.

Three easy ways to brew and strain

• Mason jar and sieve: the no-new-gear method. Line a sieve with a paper filter for the final strain.
• French press: steep right in the press, plunge, then pour through a paper filter. Great for small batches.
• Cold brew bag or pitcher with a filter insert: the least mess. Lift the bag out and you're done.

Flavor ideas

• Cinnamon cold brew: add a cinnamon stick to the jar while it steeps.
• Vanilla sweet cream cold brew: top with a splash of cream whisked with vanilla syrup, or go all the way with vanilla sweet cream cold foam.
• Marshmallow cold foam cold brew: a trend for good reason; recipe in our cold foam guide.
• Brown sugar oat: stir in brown sugar syrup and top with oat milk.

Make any syrup to the exact batch size with the coffee syrup calculator.

Troubleshooting

• Weak: use a stronger ratio, steep longer, stir at the start so no grounds stay dry, or dilute less.
• Bitter or woody: steeped too long or ground too fine. Try 14 to 16 hours and a coarser grind.
• Cloudy or gritty: grind coarser and strain through paper.
• Sour: very light beans or too short a steep. Go a few hours longer or try a medium roast.

Cold brew vs iced coffee

They're not the same drink. Iced coffee is coffee brewed hot and then chilled or poured over ice, which keeps more of the coffee's bright, fruity acidity. Cold brew never touches hot water, so it tastes rounder, heavier and lower in perceived bitterness and acidity. Iced coffee is ready in minutes; cold brew needs to be planned the day before.

Want the best of both on a hot afternoon? Make a quick iced pour-over: brew a normal recipe, but replace about a third of the water with ice in the server so the coffee chills instantly as it drips. Use a slightly finer grind to make up for the smaller amount of hot water.

Scaling up for a crowd

For a party or a week of cold brew, a large pitcher or food-safe container works well. Keep the same ratio, stir well at the start, and allow a couple of extra hours of steeping if the batch is very large. Straining is the slow part, so give yourself time, and label the jar with the date you made it.

How long does cold brew last?

As general guidance, keep cold brew sealed in the fridge. Concentrate tastes best within about a week and is commonly kept for up to two. Diluted cold brew or anything mixed with milk is best within a few days. Trust your senses: if it smells sour or looks off, pour it out.

Curious how much caffeine a glass has? It varies a lot with the recipe; our caffeine calculator gives typical estimates.

Questions people ask