How to Make Cold Brew Coffee at Home (It's Stupid Easy)

Cold brew costs $5 at the coffee shop. A week's worth costs the price of one cup if you make it at home. And it's literally just coffee and water sitting in a jar. Not complicated. Not confusing. Just cold water and coarse grounds left alone for 12-24 hours.

I make a batch every Sunday and drink it all week. I'm going to show you the exact method, and then I'm going to explain the stuff that most guides skip: what cold brew concentrate actually is, why it's different from ready-to-drink cold brew, how long it actually keeps, and the difference between iced coffee and cold brew (they're completely different and I'm tired of people getting confused about this).

The Basic Method (Really Simple)

You need:

• A jar (a mason jar works perfectly)
• Coarse ground coffee
• Cold water (filtered is better)
• Cheesecloth or a fine mesh strainer

Step 1: Add Coffee

Pour coarse ground coffee into your jar. I use a 1:8 ratio for concentrate, which means if you want to make 32 ounces of cold brew concentrate, you use 4 ounces of coffee. That's roughly 113 grams of coffee.

For a standard quart-sized mason jar, I use about 100 grams of coarse ground coffee. That's roughly one 3/4 cup or one large handful.

Step 2: Add Water

Fill the jar with cold water. Filtered water is better but tap water is fine. Use a spoon and stir it around so all the grounds get wet. Make sure there aren't any dry pockets of coffee.

Step 3: Wait

Put a lid on it and stick it in the fridge. Now wait 12-24 hours. Twelve hours gives you lighter, brighter cold brew. Eighteen hours is my sweet spot. Twenty-four hours gives you darker, more bitter cold brew.

You can leave it at room temperature instead of the fridge if you want, but cold water extracts slower than hot water, so room temperature will give you a faster result. I always use the fridge because I have time and I want bright, clear cold brew.

Step 4: Strain

After your steeping time, pour the cold brew through cheesecloth or a fine mesh strainer into a clean container. This removes most of the grounds. If you want it super clean, pour it through cheesecloth twice.

Save the grounds (throw them out) and the liquid (this is your cold brew concentrate or ready-to-drink brew depending on how you made it). Pour it into a bottle and stick it in the fridge.

That's it. You made cold brew.

Concentrate vs Ready-to-Drink: The Key Difference

This is where people get confused. Cold brew concentrate and ready-to-drink cold brew are different things.

Cold Brew Concentrate

This is made with 1:8 ratio (coffee to water). It's strong and concentrated. You can't drink it straight—it tastes like you're drinking a coffee brick. You dilute it before drinking.

Typical dilution is 1:1 or 1:2. One part concentrate to one part water (or milk or whatever). Sometimes even 1:3 if you want it lighter.

Why make concentrate? Because it takes up less space in your fridge and lasts longer. Concentrate will keep for about 2 weeks. You use a small amount each day and dilute it as you go.

Ready-to-Drink Cold Brew

This is made with 1:15 ratio (coffee to water). It's meant to drink straight from the jar or bottle. It tastes like good iced coffee but smoother because it wasn't made with heat.

Ready-to-drink cold brew doesn't last as long because it's more dilute. I usually finish a batch within 10 days. You can probably push it to 2 weeks if you're careful.

Which Should You Make?

If you drink a lot of cold coffee and you have fridge space, make ready-to-drink. If you want something that lasts longer and takes less space, make concentrate.

I alternate. Some weeks I make concentrate because I'm drinking iced lattes and I want flexibility. Some weeks I make ready-to-drink because I'm drinking it black and I want something I can just grab and go.

The Hot Bloom Cold Brew Trick

This is something I started doing recently and it actually works. Instead of using only cold water, I use a small amount of hot water to bloom the grounds for 1-2 minutes, then I fill the rest with cold water.

Here's the process:

1. Put your grounds in the jar
2. Pour a small amount of hot water (about 1/5 of your total water) and let it sit for 2 minutes
3. Fill the rest of the jar with cold water
4. Stir well
5. Put a lid on it and wait 16-18 hours (slightly less than cold-only method)
6. Strain

The hot water bloom releases CO2 and wakes up the coffee, similar to what happens when you bloom in hot pour over brewing. This gives you better extraction in a shorter time. The result is cold brew that's brighter and more flavorful even at 16-18 hours instead of 20-24.

It's a small change but it matters. Cold brew is usually darker and less complex than hot coffee. The hot bloom trick makes it closer to the complexity of hot-brewed coffee.

Mason Jar vs Cold Brew Maker

You can make cold brew in a mason jar. You can also buy a dedicated cold brew maker. Let me tell you which is worth it.

Mason Jar Method

Free or nearly free. A mason jar costs $2. A piece of cheesecloth costs $3. Total investment: $5. It works perfectly. The only downside is you have to pour through cheesecloth to strain, which takes a couple minutes and is slightly messy.

Toddy Cold Brew System

This is the OG cold brew maker. It's about $12 and it's a dedicated container with a built-in straining system. You put grounds and water in, wait 12-24 hours, and then press a button to strain directly into a cup or bottle. It's convenient.

I own one and I use it sometimes. It's not necessary but it's convenient. If you're making cold brew multiple times a month, it's worth the $12.

OXO Good Grips Cold Brew System

This is fancier than Toddy, costs about $25, and it looks nicer sitting on your counter. It has a similar button-press straining system. It's slightly less messy than pouring through cheesecloth.

If you care about aesthetics and you make cold brew regularly, this is worth it. If you just want something that works, the mason jar is fine.

Hario Mizudashi Cold Brew Pot

This is beautiful. It's a glass pitcher designed specifically for cold brew. It costs about $20. You brew directly in it, and it has a built-in fine mesh screen so you can pour straight from the pitcher into your cup without straining.

I own this one and I love it. It looks good on my counter. The straining is seamless. If you make cold brew regularly and you want something beautiful, this is my recommendation.

My Recommendation

Start with the mason jar. If you're making cold brew every week, upgrade to the Hario. The Toddy and OXO are fine but Hario is more beautiful and works just as well.

Cold Brew vs Iced Coffee (They're Different)

This is something people get confused about all the time. They're not the same.

Iced coffee is hot-brewed coffee poured over ice. You brew it hot and it cools down.

Cold brew is made with cold water and never gets hot. No heat involved at any point.

The difference matters. Cold brew extraction is slower because water is cold. You don't pull out as many of the quick-extracting compounds (tannins, harsh oils). So cold brew tastes smoother and less bitter than iced coffee, even if they're made from the same bean.

Cold brew also has less acidity than iced coffee. Some people find this makes it gentler on their stomach.

They're different drinks. Iced coffee is faster to make and tastes more like regular coffee. Cold brew takes longer but tastes smoother.

How Long Does Cold Brew Keep?

If you make concentrate, it keeps about 2 weeks in the fridge. If you make ready-to-drink, I'd drink it within 10 days. Beyond that it starts tasting stale.

Cold extends shelf life compared to hot coffee because cold slows down degradation. But it's not forever. Make a batch Sunday, drink it by the following Sunday.

I write the date on the bottle with masking tape so I remember when I made it. It sounds silly but I've definitely made cold brew and forgotten about it for 3 weeks.

Cold Brew with Milk or Water

If you made concentrate, you need to dilute it with something. Options:

Water: Straight cold brew coffee. Clean, bright, pure coffee flavor. This is what I do most days.

Milk: Cold brew with regular milk or almond milk or whatever makes a coffee-and-milk drink. Smooth, creamy, less coffee flavor. This is a latte basically.

Cream: Cold brew with heavy cream. Very rich and smooth. Actually pretty good.

Flavored syrups: You can add vanilla, caramel, whatever. If you're making this at home you probably don't want to, but it's possible.

My process: I make concentrate, and then each morning I decide whether I want it black with water, or with milk. This flexibility is why I like making concentrate instead of ready-to-drink.

My Cold Brew Recipe

Here's exactly what I do every Sunday:

1. Get a quart mason jar
2. Measure out 100g of coarse ground coffee
3. Pour the coffee into the jar
4. Add 800ml of cold filtered water
5. Stir really well so all grounds are wet
6. Put the lid on
7. Put it in the fridge
8. Wait 18 hours
9. Pour through cheesecloth into a clean bottle
10. Put it back in the fridge
11. Each morning, pour concentrate into a glass, add equal amount of water or milk, add ice
12. Drink for the next 2 weeks

This creates cold brew concentrate that's smooth, bright, and makes excellent iced coffee every morning. The whole active process is maybe 5 minutes. Everything else is just waiting.

Troubleshooting

My Cold Brew Tastes Weak

Your ratio is too weak or your grind is too coarse. Use more coffee or grind slightly finer. Or steep longer (24 hours instead of 18).

My Cold Brew Tastes Bitter

You steeped too long. Try 16 hours instead of 18 or 24. Or grind coarser. Or use cooler water if possible.

My Cold Brew Has Sediment

You didn't strain well enough. Strain through cheesecloth twice. Or use a dedicated cold brew maker with a finer mesh.

Final Thoughts

Cold brew is the easiest way to have good iced coffee all week. It costs almost nothing. It takes 5 minutes of actual work. You just have to remember to make it on Sunday. After that you have iced coffee every morning for 2 weeks.

I genuinely don't understand why people spend $5 at the coffee shop every morning when cold brew is this easy. Make a batch. Drink it black or with milk. Stop paying $35 a week for iced coffee.