What Is The Proper Chemex Coffee To Water Ratio?

Are you wondering what the right Chemex coffee to water ratio is? Make the perfect cup of coffee with the right amount of water!

Preparing of tasty coffee in chemex on table
The right Chemex ratio is one gram of coffee to 15 grams of water

If you are anything like me, you rely on your Chemex Coffee Maker to make you a delicious cup of coffee in the morning. Whether you are someone who likes French Press, cold brew, or something fast and the roasters, you have to use the right coffee beans to grams of water ratio when you brew coffee.

If you are using a Chemex filter, the right Chemex ratio is one gram of coffee to 15 grams of water. Unless you are familiar with metric measurements, it is probably better to translate this into cups of coffee.

To make one cup of Chemex Coffee, use 20 grams of coffee beans (which is about three tablespoons) and 300 grams of water. Even though you can play around with this ratio slightly, you should stick pretty close to this recipe in order to make a delicious cup of coffee. 

How can you put this recipe to work for you? 

Chemex Ratio: Making the Right Chemex Recipe

Coffee filter and coffee jug.
Follow these steps to make a Chemex coffee

If you are making pour over coffee and need a Chemex recipe, there are a few steps you should follow. First, you should get 34 grams of light or medium roast coffee beans. Then, measure 520 grams of filtered water. Using filtered water is important because this will protect the flavor of the coffee beans. 

After this, follow these steps:

  • Fill a pot with the filtered water measured from above. Use a gooseneck kettle that will let you know how hot the temperature is. Heat the water to 200 or 205 degrees Fahrenheit. 
  • After this, take out a food scale and make sure you have 34 grams of coffee. You can use an electric burr grinder to grind your coffee beans to a medium-coarse grind. This should look about the same size as kosher sea salt. 
  • After the water is done heating, place a filter in your Chemex. Then, pour in a small amount of water to get the filter wet. After this, set the water aside. Then, place the ground coffee into the Chemex. Take the Chemex to ensure the coffee grounds are even. 
  • Next, you should place the Chemex on your food scale and tare it. The scale should read 0 when you are done. 
  • Now, you should take the water and slowly pour 70 grams of water into the Chemex in a circular motion on the side of the filter. Make sure the coffee has a chance to bloom when you are done. 
  • Finally, you can pour the remaining water into the Chemex. Make sure you give the water time to go down so the Chemex does not overflow. 

Once the water is done filtering through the Chemex, you should have hot coffee in the carafe below. You should remove the filter and discard it. You might even be able to compost it. Now, you can enjoy your hot specialty coffee

One of the step of making fantastic coffee
Slowly pour 70 grams of water into the Chemex

Adjusting the Chemex Brew To Meet Your Needs

You may be able to adjust certain aspects of the recipe to meet your specific type of coffee. A few options include: 

  • If you heat the water to a higher temperature, you might be able to extract more coffee flavor; however, it may also burn the coffee, so you should be careful. 
  • If the flavor is not strong enough, you may want to grind the coffee to a finer degree to make it easier for the water to extract. 
  • If you find the coffee tastes a bit thin, you may be pouring the water too quickly into the filter. Consider slowing down the rate at which you for your water to give the coffee more time to extract. 
  • If the coffee is too strong, you may be grinding it too finely. You may want to scale back on your coffee grinder. 
woman using a coffee grinder
If the coffee is too strong, scale your coffee grinder

Remember that you can also add flavor shots to your cup of Chemex coffee. You can make your morning cup of coffee a bit more interesting. If you play around with these requirements, you should be able to make the perfect cup of coffee for yourself. 

Final Word on Chemex Coffee to Water Ratio

A Chemex is a great way to make a delicious cup of coffee in the morning; however, you also have to get the right coffee to water ratio. If you do not use enough water, your coffee may taste too strong, or you might not even make enough coffee to meet your needs.

If you use too much water, then your coffee may taste a bit thin. Remember that you can also play around with the grind and temperature of the water if you are trying to get a specific taste from your cup of coffee. 

Even though it does take a bit of practice, you can make a reliable, consistent, and delicious cup of coffee with your Chemex. Play around with the ratio a bit and see what is right for your morning cup of coffee!

FAQs About Chemex Coffee to Water Ratio

What is the right coffee to water ratio for a Chemex? 

You should combine one gram of coffee with 15 grams of water to make coffee in your Chemex. You should multiply this recipe if you are making multiple cups of coffee.

What is the right grind for my coffee in my Chemex?

Even though this is a matter of personal preference, you should start with a medium-coarse grind. Then, you can play around with the grind in order to get the right taste for you. 

Why does the water filter through my coffee so quickly?

If you find that the water is filtering through your coffee too quickly, then you should pour the water slowly down the side of the filter. This will give the water time to run through your coffee grounds before they fall into the pot below. 


  • David R

    Job experience includes extensive work as a teaching assistant, tutor, and guest lecturer and extensive employment in the healthcare field. Have published multiple research papers and numerous poster presentations on various healthcare research topics. Find David on WriterAccess.