How To Make The Perfect Cold Brew With A Chemex (Quick Guide)

Last Updated on October 16, 2021 by John Moretti

I like to brew my coffee at home, and during hot summers, a café-quality cold brew works for me. I can always rely on my Chemex to make me a perfect cuppa to beat the weather during both cold and hot summer days. 

There is an option of immersion cold brews where you let the coffee steep overnight in a container, but the result is a very dull and flavorless beverage. The slow drip brewing method extracts a variety of flavors, but it takes a substantially long time and is labor-intensive, which is why I opt for Chemex brewing.

Making Cold Brew Using A Chemex

There are several ways to prepare a cold brew, but we will talk about the Chemex brewing method. After my first cup of coffee on a warm day, I crave a cold brew, and my Chemex coffee maker is a match made in heaven for my cold brews. If you wonder how to prepare the perfect cold brew with a Chemex, this post will help with the guidelines. 

The process is not as complicated; you just put water and ground coffee in a jar and allow it to refrigerate overnight. The following morning, use a Chemex filter, pour out the cold brew from the jar, and let it run through the filter. You can then pour the brewed concentrate into a cup and add water and ice to dilute.

What Do I Need?

  • Whole bean coffee
  • Coldwater
  • A Chemex coffee maker with bonded paper filters
  • A fridge to allow it to steep at room temperature
  • A lidded container or a mason jar


Grind the coffee beans to a coarse, fine, and even grind or buy pre-grind beans from the local store if you want. You can use a burr grinder but ensure there is consistency in the coarseness to resemble sea salt.

Then add the coffee grounds to a lidded jar that can accommodate the needed amount of water. For the 170 grams of coffee grounds, use about 32 ounces or slightly under a liter of water, then screw the lid on and shake to allow the water and grounds to mix well. 

Ensure that the ratio of water to coffee grounds is subjective, depending on your tastes and preferences, and leave some room for the grounds. For instance, if you use a scale, 6 ounces or 170 grams will do; otherwise, use a quarter cup of whole bean coffee grounds. Whole beans are ideal for a tasty cold brew, and they can also be ground into coarser finer grounds, unlike pre-ground coffee.


After all is done, put the solution in a refrigerator overnight or for 12 to 18 hours for an optimal cold brew in the morning. The brew refrigeration period depends on your personal taste and preference and the type of coffee beans used for extraction. The longer you leave the mixture steep, the stronger your cold brew gets, so consider leaving it in your fridge for longer if you prefer dark, cold, and strong cuppas. The 18 hours result in a mild cold brew, and it’s recommended for most occasions. 

If you don’t have a fridge, keep the brew at room temperature and shorten the brew time, especially if your house gets hot fast to prevent over-extraction. At room temperature, off-flavors are extracted faster, so don’t over-extract otherwise, you end up with a bitter cold brew with a woody taste.

The steeping period results in a cold brew concentrate which needs to be strained and diluted before it’s ready for drinking.

Straining the mixture

After steeping, the next step is separating the coffee grounds from the cold brew, where the Chemex comes in. Put a Chemex filter in your brewer and gently stir the cold brew mixture to allow the cold brew mixture to suspend the coffee grounds, then pour out the mixture onto the Chemex filter. Use the handle of a long wooden spoon for stirring because metal spoons are known to tamper with the taste of the coffee and ensure all grounds are soaked in well. If there is any ground coffee left behind in the jar, leave it. 

Allow the liquid to drain through the Chemex filter slowly. After using the Chemex filter, run it through boiling water to rinse, tip out any liquid from your Chemex, and put the ground coffee in the brewer. After about 5 minutes, you can remove the filter paper and decant the mixture in a jar if you want. Allow the mixture to reach room temperature before proceeding to refrigerate.

Serving time

cold brew coffee

After carefully following through the coffee-making process, you get a cold brew concentrate, which I don’t recommend drinking as it is. The concentrate contains high levels of caffeine, so you decide on how best you need it diluted. I recommend using a 50/50 ratio of cold brew concentrate to water, then gradually adjusting the ratio till it tastes perfect for you. Pour out your cold brew and enjoy as you like, meaning that you can add some milk or more ice if you have a strong brew but take care not to water it down. 

Why Use A Chemex To Make Cold Brews?

A Chemex is an ideal brewer for cold beverages, but some coffee enthusiasts and amateurs wonder; why use a Chemex and not a strainer with a cheesecloth like many recipes recommend? Why can’t I use regular paper filters of pour-over cones? Chemex is preferred for making cold brews for the same reason it’s popular for brewing hot beverages. 

The Chemex has a bonded, thick filter that enables it to strain out any impurities, sediments, and fine coffee bean grounds for a delightful, smooth, and crisp cuppa. It’s the same mechanism for cold brews where the Chemex filters out all the impurities from the cold brew concentrate for a happy caffeinating experience.

The Chemex cold brew is famous for its crispness and clarity, which results in a perfect final brew, and any type of coffee beans can be used for this purpose. Whether I’m brewing for a small or large batch, the Chemex coffee maker is ideal. 


What is a Chemex?

The Chemex is a famous pour-over coffee maker that does a stellar job of making great hot coffee and ice coffee. It’s designed with a glass flask with an hourglass shape, with its neck or handles wrapped in wood using a leather tie. The Chemex is simple yet stunning in design and appeal, to the point where it’s featured in The Museum of Modern Art in New York.

How Does Chemex Work?

The Chemex is a very functional brewer as it serves as a strainer and receiver vessel at the same time. To make the perfect cold brew, most coffee gurus use a fine sieve made of mesh to drain out the coffee grounds after steeping the cold brew, but with the Chemex, it’s easier. The brewer can strain out even the finest coffee grounds and sediments, which gives me a clean, crisp, and smooth cup of cold brew with an incredible taste. 

The Chemex has thick paper filters that hold back all the fine coffee particles and impurities, making for a delightful cold brew quest. It also feels good and stylish to pour out cold brews from my Chemex on a hot summer day, especially when I have friends.

Is Ice Coffee The Same As A Cold Brew?

Unlike popular opinion, ice coffee is not the same thing as a cold brew. Cold-brew is more famous for coffee drinkers, and it takes approximately 24 hours to prepare, while ice coffee takes the same amount of time to prepare as regular hot coffee. Iced coffee has a bright and flavourful taste, and it retains most of the flavors and tastes found in the standard hot brew version. On the contrary, cold brew results in a slight acidic beverage with high caffeine levels.