How to Make Cold Brew Coffee at Home

Cold brew isn't just coffee with ice in it — it's an entirely different extraction process, made with time instead of heat. It also comes with one popular claim that's more myth than fact, and one fact that genuinely surprises most people.

Cold Brew Is Not Iced Coffee

This is the most common mix-up, and the distinction is genuinely simple once explained.

Time, Not Heat

Cold Brew

Coarse grounds steeped in cold or room-temperature water for 12-24 hours, producing a smooth concentrate that's diluted before drinking.

Hot, Then Chilled

Iced Coffee

Ordinary hot-brewed coffee, simply poured over ice afterwards — same extraction as your normal cup, just served cold.

Probably a Myth

"Cold Brew Is Less Acidic" — The Science Is Actually Mixed

It's repeated everywhere, but a peer-reviewed study measuring the actual pH of both methods found cold brew (pH 4.96-5.13) and hot brew (pH 4.85-5.10) to be statistically comparable — not meaningfully different. What cold brewing does change is which flavour compounds get extracted: fewer bitter, sharp-tasting compounds and more smooth, sweet ones, which genuinely does make it taste gentler. That perceived smoothness is real; it just isn't the same thing as a measurably lower acid content.

Rao, N.Z. & Fuller, M. (2018), Acidity and Antioxidant Activity of Cold Brew Coffee, published in Scientific Reports.

The Smooth Taste Is Deceptive — It's Genuinely Strong

A 16oz cold brew typically contains somewhere around 185mg to 205mg of caffeine — noticeably more than the same size iced coffee, thanks to the higher coffee-to-water ratio and much longer extraction time. Cold brew concentrate before dilution is stronger still. It's easy to underestimate how much caffeine you're drinking simply because it doesn't taste sharp or bitter.

How to Make It at Home

1

Use a coarse grind — the same size you'd use for a French press. Fine grounds make cold brew difficult to filter clearly.

2

Combine coarse coffee and cold or room-temperature water at roughly a 1:4 ratio for a strong concentrate (or 1:8 for a more drinkable, ready-to-serve strength).

3

Stir briefly, then leave to steep at room temperature or in the fridge for 12 to 24 hours.

4

Strain through a fine mesh sieve, cheesecloth, or coffee filter to remove all grounds.

5

If you made a concentrate, dilute with water or milk to taste before drinking over ice.

6

Store any leftover concentrate in a sealed container in the fridge for up to two weeks.

Made With Cold Brew in Mind

Medium roast, coarse grind option, ready for a long steep.

Cold Brew Coffee Beans Purpose-Built

Cold Brew Coffee Beans

Medium roast with a dedicated coarse grind option — built specifically for a long, smooth steep.

Read the Full Guide

Tea vs Coffee: Caffeine Content, Health Benefits & Which to Choose →

Related Reading

Best Coffee Beans for French Press →

Shop Coffee Beans & Grounds

Find coarse-ground and whole bean options suited to a long, cold steep.

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Frequently Asked Questions

Can I make cold brew with a fine grind if that's all I have?
It's not recommended — fine grounds are much harder to filter out completely and can lead to a gritty, over-extracted, more bitter result. A coarse grind is genuinely worth sourcing for this method.
Do I need to refrigerate cold brew while it steeps?
Either room temperature or the fridge works, though room temperature steeping is often slightly faster. If steeping for the full 24 hours or in a warm kitchen, refrigeration is the safer choice.
Why does my cold brew taste watery?
This is usually down to using too little coffee relative to water, or over-diluting a concentrate. Try increasing the coffee-to-water ratio slightly, or adding less water when diluting your finished concentrate.
Is cold brew actually better for a sensitive stomach?
Given the mixed evidence on pH, any benefit may come more from the smoother flavour and different compound balance rather than a genuinely lower acid content. Individual tolerance varies, so it's worth trying it yourself rather than assuming.
Can I make cold brew with tea instead of coffee?
Yes, cold brewing works well with tea too, typically requiring a shorter steep of around 6-12 hours in the fridge, producing a smoother, less astringent iced tea than hot-brewing and chilling.
How much water should I add to cold brew concentrate?
A common starting point is equal parts concentrate and water or milk, then adjusting to taste from there, since personal strength preference varies quite a bit from person to person.
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