How to Brew Coffee with a Chemex

Are you looking for a cleaner, brighter coffee experience? Meet the Chemex, an elegant glass vessel that isn’t just for looks. It’s also a reliable tool for brewing clean cups of coffee with complex and nuanced flavor profiles. While it requires a bit more patience and precision than other methods, the morning ritual and the flavorful coffees it produces make it worth the effort. Grab your mug and join us while we break down exactly how to master the Chemex so you can create your next favorite morning brew. 

What Is a Chemex, and How Does It Work?

The Chemex, first introduced in 1941, is a pour-over coffee brewing method with a unique glass design and thick paper filters. It takes a little extra time compared to some methods, but it gives you precise control over the brewing process to produce smooth, clean-tasting coffees. The larger-sized vessel compared to other pour-overs also makes it perfect when brewing for two. 

In a nutshell, it’s a manual brew system where you slowly pour hot water over a bed of ground coffee and essentially let gravity do the rest. 

What You'll Need 

• 42g medium (normal) ground certified organic, Fair Trade, shade-grown coffee

• 700g water

• Timer

• The Chemex

• Coffee filter

• Kitchen scale

Chemex Grind Size and Coffee-to-Water Ratio

With the Chemex’s thick bonded paper filters, the water flow is more restricted than standard filters, so a normal grind works best. If you grind it too fine, the water may stall and overextract, while grinding it too coarse may cause underextraction.

Your coffee-to-water ratio will determine how strong your cup tastes. For most pour-over methods, a common starting point is between 1:15 and 1:17, or 1 part coffee to 15-17 parts of water. Our standard recipe uses 42g of coffee to 700g of water, which is a 1:16.6 ratio, because we feel it creates a balanced cup with most coffees. However, taste is personal, so start with the recommended amount and then adjust it to suit your preferences.

How to Make Chemex Coffee: Step-by-Step 

These steps will help you brew the best cup using your Chemex.

1. Use a gooseneck kettle set at 205°F, or bring your kettle to a boil and then let it rest for 30 seconds before using it. 

2. Place the paper filter in the Chemex. If you're using a bonded Chemex filter, fold it so the three filter layers are on the spout side. 

3. Rinse the filter with hot water to remove any papery taste, then discard the water.

4. Place the Chemex on the scale and zero it. 

5. Add 42g of ground coffee to the filter and zero the scale again. 

6. Start the timer and add 150g of water (without zeroing the scale) to let the coffee bloom, which is where it absorbs water, expands, and releases trapped CO₂ gas. This is a natural part of the brewing process that many coffee lovers believe helps with a more even extraction. Then stir gently to thoroughly wet the grounds.

7. At 45 seconds on the timer, begin pouring water in slow, steady concentric circles to 450g, starting from the inside and working your way outwards. 

8. Allow the water to drain until your timer reads 1:45.  

9. At 1:45, pour more water in slow, steady, concentric circles until the scale reads 700g.

10. When the coffee has drained slightly, gently swirl the Chemex to loosen the grounds from the side, then let it finish draining, which should happen at around 4 minutes.

11. Remove the filter, pour, and enjoy!

If the Chemex becomes part of your daily routine, our bulk coffee options make it easy to always have fresh grounds on hand without running out.

3 Reasons Your Chemex Coffee Doesn’t Taste Right (And How To Fix It) 

Overextracted, Bitter Coffee

If you get a bitter taste, it may be overextracted. One common culprit is grinding your coffee too fine, which can clog the filter paper, especially with Chemex bonded filters, which are thicker than others. It can also happen if your water is too hot. Be sure to stick with a normal grind and don’t use water straight off the boil. 

Underextracted, Sour or Weak Coffee

Sour or weak coffee is often a sign of underextraction. This can happen if you use too coarse of a grind and your water rushes through the filter too quickly. It can also occur if the water temperature is too low or you skip the bloom phase. 

Stalled Brew

If the water pools in the filter and refuses to drip, your filter is clogged, typically choked by fines—tiny dust-like particles of coffee. This may still happen with a normal grind using a standard blade grinder, which is why a bistro-style burr grinder is often preferred because they create more consistent particle sizes, making it easier to dial in your recipe. 

Occasionally the heavy Chemex filters can seal against the pouring spout, creating a vacuum. If that happens, gently lift the filter paper away from the glass to burp the trapped air.  

How To Get More Out of Your Chemex

1. Using a gooseneck kettle allows you to pour more precisely, giving you more control over the flow rate and pouring pattern. 

2. Use good-tasting tap water or filter it if yours has hard, metallic, or chlorine flavors, which may come through in the coffee.

3. Weigh your coffee for precise, consistent brews. Scooping gives variable results since different roasts, origins, and grinds all have different densities.  

4. We recommend using the thick Chemex filters if you want to filter out the most oils and fines for cleaner and brighter cups. 

5. The Chemex is especially well-suited to certified organic, shade-grown Fair Trade light roasts and medium roasts, helping bring out the more subtle flavors of the origin. While you can use it to make dark roasts, the paper filter will absorb much of the natural oils, reducing the body people typically expect from a dark roast. 

Frequently Asked Questions

What are the Best Coffees for a Chemex?

Light and medium roasts shine when brewed in a Chemex. Because the thick paper filter strips the heavy oils and fine sediments that normally muddy a cup, it helps bring out the more delicate flavor notes often found in light and medium roasts, like citrus, stone fruits, or delicate florals. 

What Grind Size Should I Use for a Chemex?

A normal (medium) grind, about the consistency of table salt, works best in a Chemex. If you use a fine grind, the custom filter paper could clog and stall the brew. But if you use a coarse grind like you would in a French press, it may result in underextraction.  

How Many Tablespoons of Coffee for 3 Cups of Chemex?

We recommend using scales for accuracy. However, our recipe for the standard 3-cup Chemex uses 42g, which roughly translates into 8 tablespoons of coffee, but the actual volume will vary with the roast, origin, and grind.   

Can I Use Regular Coffee Filters With a Chemex?

Technically, yes, you can use any compatible filter in the Chemex and still make excellent coffee. However, the magic of the Chemex lies partly in its bonded filters, which are designed to filter out the oils and fines to produce smooth and balanced cups of coffee. 

Brew a Cleaner, Brighter Cup With Organic, Fair Trade Coffee and a Chemex 

Brewing with a Chemex can be a rewarding morning ritual that blends science, art, and patience to produce clean, smooth, bright cups of coffee. Because the Chemex's filter strips away oils and fines, it works particularly well at highlighting more subtle flavor notes.

This is why we recommend brewing certified organic, shade-grown Fair Trade light roasts and medium roasts, sourced through long-term partnerships with farmer cooperatives as part of our People-Centered Development approach. As a worker-owned cooperative and Certified B Corp, we build those relationships to last — and a Chemex is one of the best ways to taste the results, highlighting the nuanced flavor notes shaped by each coffee's origin.