The Perfect Chemex Coffee Ratio


Wood handle, leather cord… this thing is Fancy and I love it!

What is it?
It’s a coffee maker invented in 1941 by chemist Dr. Peter Schlumbohm to achieve the the best cup of coffee imaginable. This guy had so much going on through his career which included over 300 patents from cocktail shakers to automobiles, it’s no wonder why he wanted the perfect coffee maker.

I would want the perfect brew as well if I worked on as many projects as he has.

What makes it so special?

Coffee from a Chemex allows your coffee to be brewed with more attention to details since you are manually measuring the exact amount of coffee grounds and hot water to the filter for your taste.

Speaking of, let’s dive into the ratio you should be using for your Chemex.

Water to coffee ratio for Chemex is 1 gram of coffee for every 17 gram of water (1:17 ratio).

To calculate how much coffee you need, weigh the amount of water you want to brew and divide that by 17. That will give you the amount of coffee to grind.

Cups of CoffeeWater (grams)Water (fl oz)Water (ml)Coffee (grams)Coffee (oz)Coffee (~Tbsp)

Use the table as a reference. Depending on how potent you want your coffee you can either add more water or grounds to your cup.

What is Chemex Coffee?

Coffee made from a specific type of maker. It’s made from a one piece borosilicate glass combined with a wooden collar and rawhide tie. Patented as the CHEMEX®.

Invented by chemist Dr. Peter Schlumbohm, he studied and understood clearly the chemistry behind the extraction of flavor and caffeine from coffee beans and this is how the idea to conception of this maker was created.

Think of drip coffee but made in a really nice vessel that was designed specially to drip through a filter long enough to get the best flavor from the coffee grounds.

Why does the coffee to water ratio matter?

It matters for the flavor of your coffee. Each coffee bean has a finite amount of flavor that can be extracted and you don’t want to ruin it by not properly brewing it.

If you use too little coffee grounds, you will have a diluted, watery cup. If you use too much, you’ll have a caffeine-loaded cup of coffee that may lack in the flavor nuances of fine specialty coffee.

But like I mentioned earlier, use the table as a reference as you will have your own preference of how your coffee should taste. Start with the ratio recommendations above and adjust by a few grams until you find the perfect ratio for you.

How to Make Coffee With A Chemex Brewer

  1. Weigh out the coffee and grind to a coarseness resembling sea salt
  2. Place Chemex filter in place with the three-sided portion of the filter placed over the pouring spout.
  3. Rinse the filter and warm the vessel with hot water, discard water.
  4. Pour your ground coffee into the filter.
  5. Begin to pour a small amount of water onto the coffee bed, about two to three times the weight of the ground coffee or just enough to fully cover and saturate the coffee evenly. Stir to ensure the entire bed is evenly saturated. Wait 30-45 seconds to allow the ground coffee to release CO2.
  6. Your second pour should provide half of the total brew water in 20-30 seconds. Make sure all of the grounds are saturated and agitated. Continue to add water in ~100g increments as coffee passes through the filter.
  7. Pour in a controlled spiral motion and then slowly add water to the center of the bed to induce agitation of the coffee bed below. Avoid pouring on the filter.
  8. Allow the water to drip through the grounds entirely, remove filter, pour, and enjoy!
  9. NOTE: The brew should have taken between 3.5–4.5 minutes. If the brew was too fast, consider using a finer grind or a slower pour rate next time. If the brew was too slow, consider using a coarser grind or a faster pour rate.


Related Posts