What is Chemex?


Chemex is a beautiful-looking, very sophisticated-looking coffee brewing device. It can be used at homes, cafes, or honestly wherever you want to brew your many cups of Coffee and fascinate your audience too.

Back in 1941, a German Chemist, Peter J. Schlumbohm, invented this elegant brewing device. He combined a laboratory glass funnel with an Erlenmeyer flask, which is also widely used in laboratories in recent times. When the two were combined, an air funnel was needed to make space for the air to escape when the water was poured in. This funnel is at the front of the device.

To save you from burning your hand, he also added a wooden belt across the waist of the Chemex.

Chemex Coffee Water Ratio


1 gram Coffee to 15 grams of water.

This ratio would not mean a lot if you do not know how many grams of coffee does it take for 1 cup. However, mentioned below are a few things you need to keep in mind:

  • 1 Cup of Chemex Coffee: To make a cup of Coffee, use 20 grams of Coffee beans (or 3 tbsp. of Coffee) and hence, (20 x 15 = 300) 300 grams of Water.
  • 2 Cups of Chemex Coffee: For 2 cups of Coffee, use 34 grams of Coffee Beans and (34 x 15 = 510), therefore, 510 grams of Water.
  • 3 to 4 Cups of Chemex Coffee (max): The maximum amount of coffee you can in a normal 6-cup Chemex is 50 grams, giving you about 3-4 cups of Coffee (depending on how big your cups are). Use 50 grams of Coffee and, therefore (50 x 15 = 750) 750 grams of Water.

Everyone wants their Coffee their way. Therefore, keep in mind, you can flex between 15 to 16 grams of water per gram of Coffee, depending on how strong or light you like your Coffee.

How to Brew Coffee with a Chemex?


1. Grind Size and Brew Time:

These two usually go hand in hand. The more coarse (rough) the grind is, the faster the water will flow, which is not good. The water should take at least a couple of minutes to pass through the Coffee when using a Chemex (depending on the dose). So use a little coarse grind, too much will make the water flow too fast, and you will end up with under-extracted Coffee. However, on the other hand, if the grind is too fine, it might block the brew completely, and nothing will come out of the filter. Therefore, the key is, the finer the grind, the more Coffee and more flavor.

2. Filter:

There are a variety of filters you can use for a Chemex. We recommend you to use the bleached ones and read here why! Paper is available in different forms and that too pre-folded. It does not matter what paper filter you use, and it is important to place them correctly into the Chemex.

Mentioned below is how you should do it:

  • Put your fingers in the middle of the 3rd or 4th layer and open it, turning it into a funnel.
  • The funnel is placed on the top of the Chemex Coffee Maker and the remaining 3 layers on the side of the groove.
    • A groove is an air vent, which lets the air escape from the lower part of the Coffee Maker.

This method will prevent vent clogging and will facilitate filtration.

3. Add Grounds:

Now is the time to grind your coffee, not too coarse and not too fine for flavorful Coffee. The thickness of the filter paper and medium-sized grains will make the flow consistent. When you add the Coffee, give it a gentle shake so that it spreads evenly.

If you are using a scale, now is the time to tare!

4. Water Temperature:

Higher the temperature, more extraction, and more flavor. Experiment between 180-200 degrees F.

5. Pour Water:

Now gradually pour the water in a circular motion until you see the water reaching around a ½ inch below the top rim of the brewer. Put the water again and repeat till the water is finished. Closely monitor the water level as it drips down. As soon as you see the Coffee grounds, take out the filter and let it drain.

6. Serve:

The Chemex Carafe is an elegant-looking serving vessel, so you can bring it to the serving table or pour it in a mug and serve it right away.

Recipes You Must Try with your Coffee