Master the perfect grind size, coffee-to-water ratio, and steep time to make smooth, café-quality cold brew coffee at home.
Quick Answer
Cold brew coffee is made by steeping coarse-ground coffee in cold water for 12 to 18 hours. Using filtered water, the proper coffee-to-water ratio, and a dedicated cold brew maker helps create a smooth, naturally sweet coffee with less bitterness than traditional iced coffee.
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If you have ever ordered a smooth, chocolatey cold brew from your favorite coffee shop and wondered why yours tastes watery, bitter, or a little too “science project in a jar,” you are not alone.
Great cold brew is simple, but a few small details make a big difference. The grind size, water quality, coffee-to-water ratio, steep time, and brewing container all work together to create that rich, naturally sweet flavor cold brew is known for.
In this guide, we will walk through how to make cold brew coffee at home, how long to steep it, what coffee works best, common mistakes to avoid, and how a dedicated brewer like the RJ3 1.5L Cold Brew Maker can make the process easier from start to finish.
How to Make Cold Brew Coffee at Home
Ingredients
- 110g coarse-ground coffee
- Cold filtered water, filled to the MAX line of the RJ3 Cold Brew Maker
- Ice, for serving
- Milk, creamer, syrup, or cold foam, optional
Instructions
- Add coarse-ground coffee to the stainless steel filter of the RJ3 1.5L Cold Brew Maker.
- Slowly pour filtered water over the coffee grounds, making sure they are fully saturated.
- Secure the lid and place the cold brew maker in the refrigerator.
- Steep for 12 to 18 hours, depending on how bold you like your cold brew.
- Remove the stainless steel filter and allow any remaining coffee to drain into the carafe.
- Pour cold brew over ice.
- Enjoy black, dilute with water, or customize with milk, cream, syrup, or cold foam.
Fill. Brew. Pour.
1. Fill
Place 110g of coarse-ground coffee into the stainless steel filter.
2. Brew
Pour filtered water to the MAX line and refrigerate for 12 to 18 hours.
3. Pour
Remove the filter, pour over ice, and enjoy smooth cold brew all week.
The Best Coffee-to-Water Ratio for Cold Brew
Quick Ratio for the RJ3 Cold Brew Maker
- 110g coarse-ground coffee
- Filtered water filled to the MAX line
This creates a rich cold brew concentrate that can be served over ice or diluted with water, milk, cream, or your favorite flavored syrup.
If you prefer measuring by cups, a general starting point is about 1 cup of coarse-ground coffee to 4 cups of water. For a stronger concentrate, use slightly less water or steep a little longer.
How Long Should Cold Brew Steep?
8 to 10 Hours
Light, mellow, and mild.
12 Hours
Balanced, smooth, and great for everyday sipping.
16 Hours
Richer, bolder, and more full-bodied.
18 Hours
Strong concentrate-style cold brew, especially good for milk drinks.
For most home brewers, 12 to 16 hours is the sweet spot.
What Grind Size Is Best for Cold Brew?
Cold brew works best with a coarse grind. The grounds should look chunky, similar to coarse sea salt.
Fine coffee grounds can over-extract, slip through the filter, create sediment, and make your cold brew taste bitter or muddy. Coarse grounds help create a cleaner, smoother cup.
Cold Brew vs. Iced Coffee
| Cold Brew Coffee | Iced Coffee |
|---|---|
| Brewed with cold or room-temperature water | Brewed hot, then chilled or poured over ice |
| Steeps for 12 to 18 hours | Brews in minutes |
| Smooth, mellow, and less bitter | Brighter, sharper traditional coffee flavor |
| Great for batch brewing | Best made fresh |
| Works well as a concentrate | Usually served as-is over ice |
Why Use a Dedicated Cold Brew Maker?
You can make cold brew in a mason jar, but it can get messy fast. Between loose grounds, paper filters, strainers, and storage containers, your “easy” coffee can suddenly feel like a tiny kitchen obstacle course.
A dedicated cold brew maker helps simplify the process. The RJ3 1.5L Cold Brew Maker is designed so you can add your coffee, pour in water, steep, remove the filter, and serve from the same glass carafe.
The 1.5L borosilicate glass design gives you room to brew multiple servings, while the reusable stainless steel filter helps contain the grounds without disposable paper filters.
7 Cold Brew Mistakes to Avoid
1. Using coffee that is too finely ground
Fine grounds can make cold brew taste bitter and leave sediment in your glass. Use coarse-ground coffee for a smoother result.
2. Not steeping long enough
If your cold brew tastes weak or watery, it may need more time. Aim for at least 12 hours.
3. Steeping too long
More time is not always better. After 18 to 20 hours, cold brew can start to taste heavy or over-extracted.
4. Using poor-quality water
Coffee is mostly water, so filtered water can make a noticeable difference in flavor.
5. Forgetting to saturate the grounds
Make sure all coffee grounds are wet before steeping so the flavor extracts evenly.
6. Drinking concentrate without diluting it
If your cold brew tastes too strong, it may be concentrated. Add water, milk, or ice until it tastes balanced.
7. Storing it uncovered
Cold brew can absorb refrigerator odors. Store it covered for the freshest flavor.
Cold Brew Troubleshooting
My cold brew tastes bitter.
Likely cause: The coffee was ground too fine or steeped too long.
Fix: Use coarse-ground coffee and keep your steep time between 12 and 18 hours.
My cold brew tastes weak.
Likely cause: Not enough coffee or not enough steep time.
Fix: Use 110g of coffee in the RJ3 Cold Brew Maker and steep for at least 12 hours.
My cold brew is cloudy.
Likely cause: Fine grounds, sediment, or too much movement while brewing.
Fix: Use a coarse grind and avoid shaking the brewer while it steeps.
My cold brew tastes too strong.
Likely cause: You may have brewed a concentrate.
Fix: Dilute with water, milk, cream, or ice until it tastes balanced.
How to Serve Cold Brew Coffee
Once your cold brew is ready, you can keep it simple or turn it into a café-style drink.
- Serve over ice with a splash of milk
- Add vanilla, caramel, maple, or brown sugar syrup
- Top with cold foam
- Use as a base for iced lattes
- Blend with ice for a frozen coffee drink
- Warm gently for a smooth, hot coffee option
Best Coffees for Cold Brew
Cold brew brings out smooth, sweet, chocolatey, nutty, and fruit-forward notes, which makes it a fun brewing method for both classic and flavored coffees.
Caramel Apple Flavored Coffee
Great for seasonal cold brew recipes with apple syrup, caramel drizzle, or vanilla cold foam.
Dark Chocolate Flavored Coffee
Great for mocha-style cold brew, chocolate cold foam, and creamy iced coffee drinks.
Vermont Maple Pecan Flavored Coffee
Great for maple cold brew, nutty seasonal drinks, and smooth coffee with cozy flavor.
Breakfast Blend Coffee
Great for a classic, balanced cold brew that works with almost any creamer or syrup.
Explore more options in our coffee collection.
Cold Brew Recipe Ideas
Once you have a batch of cold brew ready, the fun begins. Use it as the base for seasonal drinks, flavored lattes, and easy at-home coffee recipes.
- Caramel Apple Cold Brew
- Vanilla Sweet Cream Cold Brew
- Maple Pecan Cold Brew
- Dark Chocolate Cold Brew
- Brown Sugar Oat Milk Cold Brew
- Pumpkin Spice Cold Brew
Tip: As new cold brew recipes are added to the blog, link them here to turn this guide into a cold brew recipe hub.
Frequently Asked Questions About Cold Brew Coffee
Is cold brew stronger than regular coffee?
Cold brew can be stronger than regular coffee, especially when brewed as a concentrate. You can dilute it with water, milk, or ice to adjust the strength.
Is cold brew less acidic?
Cold brew often tastes smoother and less acidic than hot-brewed coffee because it is extracted slowly with cold water rather than hot water.
Should cold brew steep in the fridge or on the counter?
Cold brew can steep in the refrigerator or at room temperature, but refrigerating it keeps the process simple and helps maintain freshness.
Can I use regular ground coffee for cold brew?
You can, but coarse-ground coffee is better. Regular, fine grounds may create more sediment and a more bitter flavor.
Can I make cold brew with flavored coffee?
Yes. Flavored coffee works beautifully as cold brew, especially flavors like caramel, chocolate, maple, pecan, vanilla, and seasonal blends.
How long does homemade cold brew last?
Homemade cold brew is best enjoyed within 7 to 10 days when stored covered in the refrigerator.
Why is my cold brew cloudy?
Cloudy cold brew is usually caused by fine coffee grounds, over-agitation, or sediment. Use coarse-ground coffee and avoid shaking the brewer while it steeps.
Can I use the RJ3 Cold Brew Maker for tea?
Yes. The stainless steel filter can also be used for loose-leaf iced tea and infused beverages.
Ready to Brew Better Coffee?
Whether you enjoy classic black cold brew or seasonal coffee creations, the RJ3 1.5L Cold Brew Maker makes it easy to brew smooth, café-quality coffee right from your refrigerator.
Shop the RJ3 1.5L Cold Brew Maker
Last Updated: June 2026