How to Brew with Chemex: History, Grind, and Step-by-Step Guide

If you’ve ever wondered how to make coffee with a Chemex — especially if you’ve only seen it in museums or on Instagram — this guide explains everything: its unusual history, why it makes such clean coffee, and exactly how to use one without ruining your morning brew.

To brew with Chemex, use a 17:1 water-to-coffee ratio (e.g., 30g coffee to 510g water), a grind slightly coarser than V60 but finer than French press, and follow an 8-step pour-over method including a bloom, controlled agitation, and precise water levels. The thick paper filter is key to its clean, bright cup.

The Chemex Story: More Than Just a Pretty Glass

The Chemex coffee maker wasn’t born in a café — it was invented in 1941 by German-American chemist Peter J. Schlumbohm and launched in 1942. Its sleek hourglass design wasn’t just for looks: it was part of a 1940s American art exhibition focused on the Atomic Age. By the 2000s, it had re-emerged as a cult favorite among coffee enthusiasts for its elegant simplicity and clean extraction.

Unlike many brewers, the Chemex gained attention not just for functionality but also for design. As noted in Mark Pendergrast’s 'Uncommon Grounds', “It never questioned the filter — except among intellectuals and purists.” That praise still holds: the Chemex remains one of the few brewers celebrated equally for form and function.

Why Chemex Coffee Tastes Different: Grind and Filter

The Chemex uses specially designed, extra-thick paper filters — about 20–30% thicker than those for Hario V60 or similar brewers. This thickness slows down extraction, removes more oils and fines, and results in a cleaner, brighter, and sediment-free cup. But it also means water flows more slowly, requiring adjustments in grind size and pour technique.

Chemex works best with a medium-coarse grind — slightly finer than what you’d use for a French press, but coarser than standard V60 settings. Many online guides contradict each other, but a practical approach is to start medium-coarse and adjust based on taste and flow rate: go finer if the brew is weak or fast, coarser if it’s slow or clogs.

How to Brew Coffee with Chemex: An 8-Step Guide

This walkthrough assumes you’re making 17 ounces (about 500ml) of coffee, using 30g of coffee and 510g of water. For larger batches, scale proportionally. You’ll need: fresh whole beans, a burr grinder, a digital scale, a gooseneck kettle, Chemex filters, and hot water (just off boil).

#1. Heat Your Water
Heat about 600–650g of water total: 510g for brewing, plus extra to rinse the filter and preheat the Chemex.

#2. Grind the Coffee
Grind 30g of coffee beans to a medium-coarse consistency — slightly finer than French press, coarser than typical V60. Think of it as a middle ground that allows for a steady, even flow without over-extraction or clogging.

#3. Rinse the Filter
Fold the square Chemex filter so that the three-layered side faces the spout side of the Chemex. Place it in the top of the Chemex. Rinse the filter thoroughly with hot water to remove any paper taste, then discard the rinse water. This also preheats your brewer.

#4. Add Coffee Grounds
Place the 30g of ground coffee into the rinsed filter, leveling it gently in the center.

#5. Start the Bloom
Let your water come to a boil, then let it sit off heat for 20–30 seconds to cool slightly (ideal range: ~93–96°C). Start your timer and pour just enough water (about 60–70g) to saturate all the grounds. Let it bloom for 20–40 seconds. This releases CO₂ and prepares the coffee for even extraction.

#6. Optional Stir
After the bloom, you can gently stir the slurry with a wooden spoon or chopstick to ensure even saturation. This step is optional but can improve consistency.

#7. Pour in Stages
Continue pouring the remaining water in a slow, steady spiral, keeping the water level at least 1 inch below the top of the Chemex. Aim to finish pouring by the 3:00–4:00 minute mark. Use your scale to stop at 510g total.

#8. Drain and Serve
Once brewing is complete (usually around 4:00 minutes), remove the filter and enjoy your coffee immediately. Don’t leave it sitting on the grounds.

Post-Brew Tips
To keep your coffee hot without affecting flavor, transfer leftovers to a thermos instead of reheating. Avoid placing the Chemex on a stove or using direct heat after brewing — it dulls the nuanced flavors you just worked to highlight.

Chemex Filters: Paper vs. Reusable

The original Chemex filters are made of bonded paper and are designed specifically for the Chemex’s unique shape. They’re thicker than standard filters, which contributes to the clean cup profile. Make sure to use the correct size — the 3-cup Chemex requires a different filter size and doesn’t work with metal filters.

If you prefer less waste, Chemex also offers reusable stainless steel filters. These let more coffee oils through, resulting in a fuller-bodied cup, though some clarity is lost compared to paper. Another option is cotton flannel filters, which require regular washing but are favored by some for their texture and reusability.

Cleaning the reusable filters is easy — just rinse and air dry. For the glass Chemex itself, a simple wash with hot water and dish soap is sufficient. Some users even soak it with salt and ice to remove stubborn oils, though this is optional.

Frequently Asked Questions

What’s the ideal grind size for Chemex?

The recommended grind size for Chemex is medium-coarse — slightly finer than French press but coarser than V60. It should allow for a brew time of around 4 minutes with proper water flow. Adjust based on taste and speed: finer for slower flow or weak flavor, coarser for faster flow or bitterness.

How much coffee do I use for Chemex?

A standard ratio is 17:1 water to coffee by weight. For example, use 30g of coffee with 510g of water to make about 17 ounces (500ml) of coffee. You can scale this up or down depending on your Chemex size and desired yield.

Do I need to rinse the Chemex filter?

Yes. Always rinse the Chemex filter with hot water before brewing to remove paper taste and to preheat the vessel. Discard the rinse water before adding coffee grounds.

Can I use a metal filter in my Chemex?

Chemex sells a special stainless steel reusable filter that fits most models, but not the 3-cup size. It allows more oils through than paper, changing the cup profile. The standard Chemex design works best with the proprietary thick paper filters.

How do I clean my Chemex?

Clean the glass Chemex with hot water and dish soap. For a deeper clean, some users soak it with salt and ice to remove coffee oils. The filters are single-use paper but reusable metal and cloth options are also available.

Recommended FrontStreet Coffee for Chemex Brewing

For Chemex brewing, try FrontStreet Coffee’s Ethiopia Yirgacheffe for bright floral and citrus notes, or their Colombia Huila for balanced caramel and nutty tones. Both single origins highlight the clean cup profile that Chemex is known for. Freshly roasted within 5 days · Orders placed before 17:00 ship the same day · Next-day delivery across most of Guangdong Province.