What is Chemex?

The Chemex is a type of manual pour-over coffee brewer. It comprises one solid piece of glass with a conical shape and a narrow neck adorned with a wooden collar held in place by a leather strap. It uses special Chemex paper filters that are double-bonded, meaning they're thicker than typical coffee filters. This gives the Chemex the ability to produce a clean and flavourful cup of coffee, as the thick filter removes most of the oils and sediment from the coffee, resulting in a bright and smooth brew.

The Chemex is a truly iconic and beautiful brewer that is instantly recognisable. Coffee enthusiasts consider it a classic because of its aesthetic design and ability to brew delicious, consistently excellent coffee.

How to Make a Perfect Chemex Brew? 

One of the best things about a Chemex is its simplicity. It has the ability to get fantastic results with little effort. Here's how it works:

Materials Needed:

  • Chemex coffee maker
  • Chemex paper filter
  • Coarsely ground coffee beans
  • Hot water (just off boiling)
  • Scales
  • Timer


Prepare the Filter:

  • Open a Chemex paper filter and place it in the top of the Chemex, ensuring that the side with multiple layers is facing the spout.

Rinse the Filter:

  • Before adding coffee, pour some boiling water through the filter to rinse it. This vital step helps remove any paper residue and preheats the Chemex.

Add Coffee Grounds:

  • Measure the desired amount of coarsely ground coffee and add it to the rinsed filter. A general guideline is 60g of coffee to 1Lt of water. But feel free to dose up or down depending on your preferences.

Bloom the Coffee:

  • Start a timer and pour a small amount of hot water (about two to three times the weight of the coffee) evenly over the coffee. This initial pour allows the coffee to bloom as gases are released, causing the coffee grounds to puff up and expand. Let it bloom for about 30 seconds.

Continue Pouring:

  • Gradually pour the remaining hot water in a controlled and circular motion, starting from the centre and moving outward. Ensure that all the coffee grounds are saturated evenly. Maintain a steady pour to control the water flow.

Control the Brew Time:

  • The total brew time for a Chemex typically ranges from 3 to 4 minutes. Adjust your pouring rate to reach this target brew time. You can experiment with the brew time to achieve your preferred coffee strength.

Remove the Filter:

  • Once the brewing process is complete, carefully lift the filter with the used coffee grounds and discard it into your food compost bin.

Who Invented the Chemex?

Dr. Peter Schlumbohm, a German chemist and inventor, created the Chemex coffee maker. After serving in World War I, he pursued education, ultimately earning a chemistry doctorate from the University of Berlin. He supported himself with inventions, notably selling a vacuum bottle design to THERMOS. Schlumbohm held over 300 patents, influenced by the Bauhaus design school, aiming to improve functionality and aesthetics. His blend of design and chemistry led to the creation of the Chemex coffee maker.

As a chemist, he understood the chemistry behind extracting flavours, oils and aromas from coffee beans. Initially, he created a dual-bonded filter paper to achieve a consistently perfect and sediment-free extraction. Then, he crafted an hourglass-shaped container out of non-porous glassware commonly used in labs, ensuring the coffee's flavour wouldn't be affected. When used together, the result was a superb coffee with incredible clarity of flavour. 

When released in 1941, it became an instant hit. Typical of the Bauhaus style, it was pure in form and function. In Schlombum's own words, with a Chemex: "Even a moron can make good coffee".

Chemex in Pop Culture 

The sleek design of the Chemex, in addition to the fantastic results of its brewing, made the brewer universally loved. The Chemex has gone on to adorn both museums, film sets and novels. Here's a list of some of the places it has popped up:

  • The Museum of Modern Art (MoMA, NY): In 1943, MoMA displayed it as part of a collection of "best-designed products". It remains on display in their permanent collection to this day. 
  • From Russia, with Love: Ian Flemming wrote that James Bond made his coffee using a Chemex in the 1957 novel From Russia, with Love.
  • Friends: The Chemex can be seen in Monica and Rachel's kitchen in multiple Friends episodes.
  • Mad Men: The main protagonist of the hit show, Don Draper, had a Chemex in his kitchen.
  • Brooklyn 99: Detective Charles Boyle can be seen brewing with a Chemex in multiple episodes of this show.

How Do You Clean a Chemex?

  1. Once cool after use, wash the Chemex's top half using warm, soapy water. Clean the hard-to-reach bottom half using a soft-bristled brush with dishwashing liquid. Rinse well after you do this and allow to air-dry or dry using a soft, lint-free cloth. 
  2. The Chemex is also dishwasher safe. Just remove the wooden collar and make sure it is securely upright. 
  3. Here's a hack for the Chemex that has a bottom half that's stained and well-loved. Start by ensuring that your Chemex is at room temperature. Then, fill the bottom with a handful of ice. After that, add four teaspoons of salt, one tablespoon of water, and an optional tablespoon of lemon juice.
  4. Swirl the mixture vigorously for one minute. The citric acid and salt will work together to remove coffee stains, while the water prevents the glass from getting scratched. Empty the contents and rinse well with cold water. Rinsing with hot/boiling water may cause the cold glass to crack! 
  5. You can repeat this step as needed.

Although it looks great and has an impressive story, at the end of the day, the Chemex is just a coffeemaker. But it excels at what it does best - making delicious coffee. This is why coffee enthusiasts love it. While other coffee makers may also produce delightful coffee and do it faster, that is irrelevant. The Chemex is not your typical weekday morning coffee maker; it's more suited for weekends when you have time to sit back, relax and savour the pure flavour of your coffee.