pinterest tag

1 Chemex Ratio To Make Brewing With A Chemex Crazy Easy

chemex coffee brewer with coffee in carafe sitting on wood table with white background, chemex ratio, brewing with a chemex

Heads up: This content is reader-supported, meaning we may earn a small commission if you click on some of our links.

So you got yourself a shiny new Chemex brewer. Congratulations! Brewing with a Chemex is a fun and aesthetically pleasing experience, but it also results in a deliciously clean cup.

But if your brews aren’t living up to the grand expectations you had for your beautiful new brewer, it might be that you aren’t using the ideal Chemex ratio.

The ratio for pour over can be a bit tricky to nail, especially when switching between brewers. Here, we’ll help you master the proper Chemex ratio for your taste and improve your overall experience brewing with a Chemex.

So, let’s get brewing.

Chemex Ratio

Before we get to brewing with a Chemex and the best Chemex ratio, let’s first look at pour over coffee and the methods to the madness.

What Is A Pour Over Coffee?

Pour over coffee refers to a manual brewing method that involves pouring hot water over coffee grounds through a filter in a dripper over a carafe or mug.

Or, in this case, a single unit made of tapered glass.

While pour over coffee originated in Europe and has been around for centuries (some credit Germany’s Melitta Bentz for her 1908 invention of the paper coffee filter), it has gained popularity worldwide.

The pour over method, including brewing with a Chemex, is a very straightforward coffee brewing process, so it’s super popular worldwide.

But how is pour over coffee different from drip? While pour over is similar to drip coffee brewing, the slow, manual process sets it apart. Most drip coffee is brewed with an electric brewer and is a hands-off process.

The slow, manual brewing process provides a relaxing experience each morning and ensures that all of the flavor nuances are appropriately extracted from the beans. The result is a complex, savory cup of coffee.

Learning how to brew pour over coffee is a fun process involving several adjustable variables like grind size, coffee to water ratio (or Chemex ratio for today’s purposes), water temperature, and, of course, the type of coffee bean used.

silhouette of hand holding a chemex with cactus and sun setting in background, What is a pour over coffee

The Chemex Origin Story

The Chemex is a coffee brewer invented by chemist Dr. Peter Schlumbohm in 1941, who had an obsession with making everyday objects more functional, easy to use, and beautiful.

We think he nailed it with the Chemex. It is, by far, the most attractive of any pour over brewer on the market, in our opinion, and the design has remained virtually unchanged since its inception. 

Yep, beautifully tapered glass, a wood handle, and a leather cord still resonate with people today. (us included)

It was designed to make brewing the perfect cup of coffee an easy and enjoyable experience. And brewing with a Chemex is indeed both fun and simple to master.

However, several variables, like the Chemex ratio, go into brewing that perfect cup, so let’s take a closer look at a few of these.

hand pouring ground coffee into chemex brewer with moistened filter sitting on scale beside plants and grinder, pour over grind setting
grind size for chemex

Grind Size For Chemex

Getting the grind right is crucial to achieving a perfectly brewed cup when brewing with a Chemex. The grind size will influence how quickly the water passes through the coffee grounds.

Too fast, and you’ll get an under-extracted brew. Too slow, and you’re left with a bitter, over-extracted cup. So, what’s the best grind size for Chemex?

The best grind for Chemex, and the ideal pour over grind setting across the board, is medium or medium-fine. Yep, that is super vague and will require some experimentation.

fellow opus grinder
The Fellow Opus Grinder

The grind size for Chemex should have a coarseness that resembles sea salt. It is slightly more coarse than what you’d use for drip coffee.

But that’s half the fun of brewing with a Chemex and learning the best Chemex ratio. Coffee flavor is, at its core, a matter of personal preference, so the subtle nuances achieved with slight grind adjustments will hit each person differently.

Start with medium and adjust from there.

Need to step up your grinder game? No problem. Check out our picks for some of the best grinders for pour over coffee.

chemex brewing coffee on scale beside gooseneck kettle, Coffee to water ratio for pour over
pour over ratio

Pour Over Ratio

Like every other type of coffee, pour over coffee requires some finessing to get the coffee to water ratio right for your taste.

We typically use a 1:16 coffee to water ratio. In other words, for a 10-cup Chemex brewer, that is 50g of ground coffee and 800g of filtered water. Start here and adjust as desired.

If this is too strong or weak for your taste, try brewing with a Chemex ratio between 1:14 and 1:18 for best results. This ratio range will work as a Chemex ratio for 2 cups of coffee or any amount you desire, making it super easy to use for all batch sizes.

So now that you’ve got the Chemex ratio down, what is the best water temperature for pour over coffee?

Water temp for pour over coffee
temperature for pour over coffee

Temperature For Pour Over Coffee

The ideal water temperature for pour over coffee is around 205 degrees Fahrenheit or about 30 seconds off the boil. If you’re lazy in the morning like us, skip the thermometer and wait 30 seconds to start brewing once your kettle boils.

Or, if you’re fancy, get yourself a kettle with a temperature setting for optimal brewing with a Chemex.

But which coffee bean is best for pour over coffee?

Best Pour Over Coffee Beans

While some coffee brewing methods yield a better result with a particular type of bean (like dark roast beans and espresso), this is not the case when brewing with a Chemex.

The good news is that the best pour over coffee beans are whichever beans you like the best. 

Brewing with a Chemex means extracting even the most subtle flavor nuances, making it ideal for sampling various roasts. So, don’t be afraid to experiment with your Chemex ratio and try several different types of coffee beans to determine your preferences.

Now, let’s get to the fun part.

close up of coffee filter lifting from chemex and dripping into carafe, How to make coffee with Chemex

How To Make Coffee With A Chemex

Pour over coffee is incredibly easy to make, especially when brewing with a Chemex. That said, a few pieces of equipment make the brewing process even simpler.

Here’s what you’ll need to make coffee with a Chemex:

  1. Gooseneck Kettle
  2. Chemex brewer (10-cup model recommended)  
  3. Paper Filter
  4. Scale
  5. High-quality coffee beans (50g)
  6. Burr Grinder
  7. Filtered water (800g)

We recommend purchasing the largest brewer (10-cup), as the price difference is negligible, and it will afford you the flexibility to brew a bigger batch as needed.

Step 1: Heat the Water

Set the kettle over high heat (or on an electric kettle base) and bring the water to a boil.

ramekin of ground coffee on acaia scale from above, Best pour over coffee beans

Step 2: Measure & Grind Coffee

While the water is heating, use your scale to weigh 50g of coffee (for a 1:16 Chemex ratio) and grind to a medium consistency. 

The grind size will resemble sea salt.

This grind is finer than what you’d use for cold brew or French press but coarser than that for drip coffee. You’ll want to use a good-quality burr grinder to achieve a consistent grind.

Step 3: Prep Brewer

Unfold your Chemex filter and make sure that the triple-fold portion faces the pour spout, laying across without obstructing it.

Once the water boils, wet the filter paper first and discard the wetting liquid before brewing. This process removes any woodsy paper flavor from the final product.

This step also warms the brewer and helps achieve a consistent brewing temperature.

Add the ground coffee to the filter and gently shake it to level the grounds. Then set the Chemex on your scale, and tare (or zero) the scale.

woman in grey la marzocco t-shirt brewing coffee with a Chemex on a black scale, How to make pour over

Step 4: Brew Coffee

Bloom the coffee first by pouring about twice the amount of water as there is coffee (in our case, 100 grams) to saturate the grounds thoroughly

Start in the center and gently pour in concentric circles outward. Stop when the water flows into the carafe. 

Wait 45 seconds. We recommend using a timer, as this step is critical to achieving the absolute best brew.

(Blooming the ground coffee allows it to de-gas and release carbon dioxide. The grounds will bubble up and create space for the water to interact with the ground coffee. The more interaction, the better the resulting brew will be.)

Begin brewing by pouring water in a slow, circular motion, starting at the center and working your way outwards before spiraling back toward the center. 

Add about 200 grams of water during each pour, allowing the coffee to percolate through the grinds until the slurry is approximately 1 inch from the bottom of the filter.

Repeat this process until the scale reaches 800g. Allow water to percolate completely through the grounds. Total brewing time should take about 3 ½ – 4 ½ minutes.

close up of coffee in a carafe dripping, The perfect pour over

Step 5: Enjoy Pour Over Coffee

Discard the used coffee grounds once all of the water has drained through the filter. Do not attempt to release additional water from the filter (by squeezing, etc.), as this may result in an over-extracted brew and negatively impact the flavor.

Serve the coffee immediately for the best flavor, and savor the fruit of your (minimal) labor.

That’s it!

See how easy brewing with a Chemex is? Adjust your Chemex ratio to achieve the optimal flavor for your tastes, and have fun with it!

Remember that different varieties of coffee may require slight adjustments to your grind size and ratio, so don’t be afraid to experiment to find that perfect brew.

So grab that gorgeous Chemex and get to it!


Heather Calatrello

Heather Calatrello owner of ShedLight Coffee Roasters