The Best DIY Cold Brew (Technically Isn’t Cold Brew)

Jun 27, 2023

A delicious glass of iced coffee made with cold-brew concentrate and milk might be the perfect refresher. Making your own at home with one of our cold-brew coffee maker picks is the method we recommend, but the internet is rife with hacks you may be tempted to try using items you’re likelier to have on hand, such as a Mason jar or a French press.

OXO’s cold-brew coffee maker produced the strongest, boldest coffee of any model we tested. It’s also easier to assemble than the competition.

Unfortunately, we found that these guerrilla methods are messy and deliver subpar results. But during our testing, we stumbled upon a cold-coffee technique that outshined them both: Japanese-style iced coffee.

Also known as iced filter coffee, it’s technically not cold brew at all, delivering a brighter, more delicate flavor. We found it to be a quicker, tidier, and more foolproof way to produce a less intense jolt of cold caffeine that even tastes great black. All you need to make Japanese-style iced coffee is a kitchen scale, a pour-over coffee maker, and a filter. I tested the method using the same Chemex Six Cup Classic Series that I’ve brewed my daily hot coffee in for years.

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As gorgeous as it is user-friendly, the Chemex makes several cups of coffee at once, and it produced a delicious, bright brew that our testers loved.

OXO’s cold-brew coffee maker produced the strongest, boldest coffee of any model we tested. It’s also easier to assemble than the competition.

As gorgeous as it is user-friendly, the Chemex makes several cups of coffee at once, and it produced a delicious, bright brew that our testers loved.

Japanese-style iced coffee is brewed just like hot pour-over coffee, except that ice is placed in the cup or carafe below so that the steaming brew is simultaneously cooled and diluted upon contact.

Because Japanese-style iced coffee is brewed hot, the process only takes a few minutes, and it’s ready to drink immediately over fresh ice. Cold-brew concentrate, in contrast, requires at least eight hours to steep and is meant to be diluted with water or milk before drinking.

To test the method, I used this recipe (video) for iced filter coffee from award-winning barista James Hoffmann. I dumped 400 grams of ice into the bottom of my Chemex, lined the top with a filter, and added 65 grams of ground coffee—a little more than I would use for hot coffee to make a more concentrated brew. Then, I slowly poured 600 grams of near-boiling water over the top. (Placing the carafe on a kitchen scale first made all of that measuring quite easy.)

I learned that this method can be forgiving. While I was precise in my measurements, I only half-followed Hoffmann’s very specific directions for stirring the bloom. And though he suggests using a fine grind of coffee, I accidentally used a coarser grind and still loved the way it tasted.

After you’re done brewing, cleanup is easy-breezy. Just as when I make hot coffee in my Chemex, the grounds are neatly enveloped in the paper filter, requiring nothing but a quick grab and toss into the trash or compost. Other than that, I just give my Chemex a daily rinse, and scrub it with dish soap about twice a week.

However, if all of that sounds too complex, or you already have or prefer a drip coffee maker, the Zojirushi Zutto, one of our picks for best cheap coffee maker, brews Japanese-style iced coffee automatically.

A small, barebones brewer that makes great-tasting hot coffee and offers easy-to-follow instructions plus measurements for brewing iced coffee.

Whichever way you make it, Japanese-style iced coffee is delightfully light and as enjoyable as a brisk iced tea—and near-opposite to the murky cold brews I tested in a French press and a Mason jar. I actually prefer drinking iced filter coffee straight from the carafe, even though I always take my hot coffee with milk.

“Japanese-style iced coffee has more clarity than cold brew, which tends to be stronger and muddier,” says kitchen editor Gabriella Gershenson.

Like all cold-brew methods, making cold brew in a French press entails dumping grounds and cold water into a vessel and waiting several hours before straining. Although you’ll probably want to play with the specifications to find your perfect brew, we went with a water-to-coffee ratio of 4.5:1—which we also used when testing cold-brew coffee makers—and let the grounds steep for 12 to 24 hours.

What comes next is the messier part: plunging the press, then filtering the brew through a cheesecloth-lined strainer into another vessel below. (You can just plunge and be done with it, but expect a particularly muddy concentrate if you do.)

The whole process wound up dirtying several pieces of equipment and left behind a press that was at least half-full of wet grounds—which I not only had to scoop out by hand, but left little room for liquid. I used a 32-ounce French press, which ended up yielding less than 16 ounces of concentrate.

According to our guide to cold-brew coffee makers, one serving of coffee consists of 2 ounces of coffee concentrate diluted with 4 to 6 ounces of water or milk. By that measure, a 32-ounce French press produces enough cold brew for a little under eight servings. Depending on the size of your household and how much coffee you drink, this method could negate the big-batch advantage of making cold brew in the first place.

Flavor-wise, the French press cold brew lacked complexity and boldness; when I mixed it with milk, it reminded me of the slapdash iced coffee I sometimes concoct with leftover hot coffee from the previous morning. It also didn’t have the pleasingly rich body I’ve achieved when using our top-pick cold-brew coffee maker, which turns out larger quantities of reliably robust concentrate with a more streamlined cleanup.

It’s pretty simple to add coffee grounds and water to a Mason jar, then let it steep for a day. To test this cold-brew method, I used 1 ounce of grounds for every cup of water and a 64-ounce wide-mouth jar for a larger yield.

Although this produced more concentrate than the 32-ounce French press (just under 24 ounces), it was considerably messier—unlike French presses, Mason jars don’t come with plungers to compress (and thus better contain) the grounds. However, you may want to experiment with putting the grounds in a nut-milk bag or extra-large reusable tea bag, which I did not try.

As with the French press, I strained the Mason jar concentrate through a cheesecloth-covered sieve. (You can repeat this step for extra filtration, but I’m not a fan of extra work.) I found that this technique simultaneously produced the weakest flavor and the muddiest body; the former because I used less coffee per water than other recipes, the latter due to opting out of a second filtration.

Different brewing methods, flavor profiles, and ease of cleanup aren’t the only qualities that separate Japanese-style iced coffee from cold brew. Here are some other factors to consider:

Making ahead versus à la minute brewing: One of the biggest benefits of cold brew is that you can make a large batch to nurse throughout the week. But to do that, you have to plan ahead, as cold brew coffee needs at least 8 hours to steep.

A benefit of Japanese-style iced coffee is that you can make it on the spot. I also adore the novelty of the brewing process, especially watching the ice melt as the hot coffee trickles over it. Now that I’ve gotten the hang of how to do it, I’m looking forward to showing it off the next time company comes over.

Low acid versus high antioxidant: The jury seems to be perpetually out on the health benefits of coffee, but at least one study has shown that cold-brew coffee is less acidic—and thus may be more tolerable to those with acid reflux and similar issues—than hot coffee. (The same study found that hot coffee had higher antioxidant activity.)

Cost: According to our tests, making your own cold brew in a Mason jar or a French press can cost up to twice as much as making iced filter coffee.

For the sake of easy math, let’s say your beans cost $10 per pound. According to the iced filter coffee recipe (video) I followed, 65 grams of ground beans makes about a liter of coffee. (This ratio is similar across several recipes I found and isn’t far off from my usual hot-coffee ratio of 55 grams to a liter.) That breaks down to a little over five 6-ounce servings of iced filter coffee at about 25¢ per serving.

Gauging the cost of cold brew is trickier. Different recipes call for different water-to-coffee ratios, and different methods can produce different yields.

The recipe I used for Mason jar concentrate has a water-to-coffee ratio of 8:1, yielding 24 ounces of concentrate from 151 grams of coffee. This amounted to about 28¢ per cup after it was diluted—not much more than the Japanese-style iced coffee, but it was also the coffee that I liked the least. Making cold brew with a 4.5:1 ratio, as we did for the French press, would nearly double the cost per serving.

This article was edited by Gabriella Gershenson and Catherine Kast.

Rose Maura Lorre

Rose Maura Lorre is a senior staff writer on the discovery team at Wirecutter. Her byline has appeared in The New York Times, Esquire, Salon, Business Insider, HGTV Magazine, and many more. She lives in New Jersey with her husband, her daughter, one dog, two cats, and lots and lots of houseplants.

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