Making cold brew is one of those craft activities that is steeped in mystery until you do it for the first time and see how simple it is. When we talk to our customers who ask about making cold brew at home and explain the process we watch as they become surprised at how ridiculously easy it is — and how overdue they were to try it.
This is a short guide on how to make great cold brew at home, with almost no equipment, using beans you probably already own. If you've been intimidated by this or thought it required special gear, consider this your permission to stop overthinking it.
What Cold Brew Actually Is
Cold brew is exactly what it sounds like: coffee brewed with cold water instead of hot. That single change — the temperature — transforms the resulting cup in ways that surprise most people the first time they try it.
Hot water is aggressive. It extracts flavor fast, pulling out acids, sugars, and bitter compounds in a specific order over a few minutes. This is why timing and technique matter so much in pour-over or espresso — you're racing through a short, high-temperature window where small changes make big differences. Small margins for error.
Cold water extracts slowly. Over 12 to 18 hours at room or fridge temperature, it pulls out sugars and aromatic compounds gently while leaving most of the acid and bitter compounds behind. The result is a coffee that's smoother, sweeter, and lower in acidity than anything you can brew hot. It's also much more forgiving — you are unlikely to over-extract cold brew the way you can easily over-extract a pour-over.
Good cold brew tastes like chocolate and caramel and a little bit of something you can't quite name. Bad cold brew tastes too strong or muddy. The difference between them is almost entirely in the beans and the ratio, both of which are easy to get right.
What You Need
You don't need a special cold brew rig. You don't need a Toddy system. You don't need a Hario filter tower. All of those work fine, but they're unnecessary. Here's what you actually need:
A large jar or pitcher. A 64-ounce mason jar is ideal because it's the right volume, has a wide mouth for straining, and doesn't leak if you tip it. Any large container with a lid works.
A fine mesh strainer and a paper coffee filter. Or a fine mesh strainer and a piece of cheesecloth. Or just a nut milk bag. You need something to separate the grounds from the liquid at the end, and you want it fine enough to catch the fines without being so fine it takes an hour to drain.
Coffee. Coarsely ground coffee, the higher the quality the better. We'll get to the ratio.
Cold, filtered water. Tap water will work if your tap water is good. If it isn't, filtered is better. The water quality matters more in cold brew than in hot brewing because the long steep time lets any off-flavors in the water fully integrate.
That's it. No machine, no specialty gear needed.
The Bean and the Grind
This is where most of the quality of your cold brew is decided.
Use a complex roast. When choosing coffee beans for cold brew, use a roast that has some complexity to it. One that has balance between two or more flavors. We find that when we use a relatively complex roast then the complexity does shine through in the final cold brew.
We use our own Dark roast for our cold brew and we have had really good results with it. This coffee makes an interestingly layered cold brew because of the addition of Rwandan beans which add that complexity we're talking about. For a lighter cold brew, use a complex light roast and you'll likely have good results.
A side note: Cold brew is super forgiving so it's a great way to use old beans. If you have a few bags lying around or a bag that you just didn't get into, save those beans and use them for cold brew. It's a good way to use beans that you don't love hot brewed. You'll still end up with something worth drinking and put those beans to good use!
Use a coarse grind. Think breadcrumbs or kosher salt. This matters for two reasons: coarser grounds extract more slowly, which is what you want over a long steep; and coarser grounds are much easier to strain out at the end. A too-fine grind will give you a gritty, over-extracted cup and a difficult straining process.
If you're buying pre-ground, ask for cold brew grind. If you're grinding at home, go coarser than you think — it should look rougher than what you'd use for a French press.
The Recipe
There are roughly a thousand ratios on the internet. Here's ours, which we've landed on after a lot of jars:
- 1 cup (about 100g) coarsely ground coffee
- 4 cups (about 1 liter) cold filtered water
- 12–18 hours steep time
- Room temperature or fridge — either works
This produces a concentrate. You'll cut it with water, milk, or more ice when you serve it, usually 1:1. If you want a ready-to-drink strength instead of a concentrate, use half the coffee — about ½ cup of grounds to 4 cups of water — and skip the dilution step.
The steps:
- Put the coarsely ground coffee into your jar.
- Pour the cold water over the grounds.
- Give it a good stir to make sure every ground is wet.
- Put the lid on. Leave it on the counter for 12–18 hours, or in the fridge if your kitchen is warm.
- When the time's up, strain through your mesh strainer lined with a paper filter or cheesecloth. Don't press the grounds — just let it drain. Pressing will squeeze out bitter compounds you spent 16 hours avoiding.
- Transfer the strained liquid to a clean jar or bottle. Refrigerate.
It'll keep for a week in the fridge, though in our house it rarely lasts more than four or five days.
How to Serve It
Our go-to serve: a tall glass, ice to the top, cold brew concentrate to the halfway mark, cold water or milk to fill. Stir. That's it.
If you want to get fancy, you can add a splash of simple syrup or a small amount of sweetened condensed milk for a Vietnamese-style iced coffee. A dash of vanilla extract works. A splash of oat milk is always good. It's forgiving enough to experiment with. I've made countless glasses of cold brew with milk and sweetener and I try something different every time. 80% of the time it's delicious.
Troubleshooting
Too weak? More grounds next time, or steep longer (up to 20 hours). Also double-check you used a coarse grind — fine grinds actually extract less into the cup because they compact and stop flowing.
Too bitter? You probably over-steeped, over-pressed during straining, or used too much coffee. Try less coffee, shorter steep, and let the grounds drain without pressing.
Gritty or muddy? Your filter wasn't fine enough. Add a paper filter on top of your mesh strainer next time.
Flat or boring? Try a different bean. You likely choose a bean that just wasn't complex enough.
One Last Thing
People sometimes treat cold brew as a lesser coffee — something you make when it's too hot for the real thing. We disagree. When the weather turns and the air's warmer and you want something sweet and smooth and easy, a glass of cold brew made from good beans is one of the best drinks coffee can give you.
It also happens to be the most forgiving, lowest-effort coffee method we know. Five minutes of active work. A bag of good dark roast. One jar. A day of patience.
If you try it this week, we'd love to hear how it goes. Tag us on Instagram at @white.whale.coffee or just reply to The Stowaway — we read everything that comes back.
Either way: cold brew season is open. Welcome aboard.
