The Chemex is a classic pour-over brewer known for its elegant design and remarkably clean cup. Invented in the 1940s by chemist Peter Schlumbohm, it combines form and function in one of coffee's most enduring tools. The thick filter removes more oils and sediment than other pour-over methods, producing coffee that tastes bright, smooth, and clean. Many people swear that a Chemex makes the perfect cup of coffee.
If you landed on this page first, you may want to start with our Complete Guide to Pour-Over Coffee for a deeper look at why pour-over brewing creates such clarity and control.
What Makes the Chemex Different
The Chemex stands apart because of its extra-thick paper filter, about 30 percent thicker than most. That filter traps more oils and fine sediments, resulting in coffee with a crystal-clear body and elevated brightness. The shape of the Chemex also contributes to its distinctive flavor profile: the wide neck and hourglass body allow heat to dissipate slowly, keeping the brew consistent from start to finish.
The result is a cup that's smooth, aromatic, and free of bitterness. It's perfect for those who prefer nuance and clarity over heavy texture and thick mouthfeel. If you prefer a fuller, richer cup with more body, the French Press or AeroPress may be worth exploring alongside it.
What You'll Need
- Chemex brewer (6-cup or 8-cup models are most common)
- Chemex paper filter (bonded square or circle)
- Freshly roasted whole bean coffee
- Burr grinder (for consistent grind size; see our grinder guide if you're not sure where to start)
- Gram scale
- Gooseneck kettle (for controlled pouring)
- Timer
- Filtered water heated to the appropriate temperature for your roast (see below)
Recommended Recipe
This recipe makes about two medium cups of coffee. The Chemex scales easily, so increase proportionally if you are brewing for more people.
- Coffee to Water Ratio: 1:16
- Coffee: 40 grams
- Water: 640 grams total
- Water Temperature: see roast-based temperature guide below
- Brew Time: 4 to 5 minutes total
Step-by-Step Chemex Brewing Instructions
1. Prepare Your Filter and Brewer
Open the Chemex filter so that three layers are on one side and one layer on the other. Place it in the brewer with the thicker, three-layer side facing the spout. Before adding coffee, insert a chopstick, straw, or thin spoon handle into the spout to keep a small air gap during brewing. This prevents the filter from collapsing against the spout and stalling the brew mid-pour. Rinse the paper filter with hot water to preheat the Chemex and help the filter stay in place. Discard the rinse water before adding your ground coffee.
2. Measure and Grind
Weigh 40 grams of coffee and grind it medium-coarse, slightly finer than for a French Press but coarser than for a Kalita Wave or Hario V60. The grind should feel like coarse sand or kosher salt. For more detail on grind size across brew methods, see our Coffee Grinding Guide.
3. Add Coffee and Start Your Bloom
Add the ground coffee to the filter and shake gently to level the bed. Start your timer and pour 80 grams of water (twice the weight of the coffee grounds) evenly over the grounds to saturate them completely. Allow the coffee to bloom for 45 seconds as it releases CO2. If your beans are within three days of roasting, extend the bloom by an additional 20 to 30 seconds to allow the extra CO2 to fully escape before continuing your pour. You'll see the bed sink slightly when it's ready.
4. Continue Pouring Gradually
After the bloom, pour the remaining water slowly and evenly in small, steady amounts. Aim to keep the coffee bed evenly saturated without over-agitating the grounds. Pouring too aggressively or from too great a height can push fines to the bottom and slow the drawdown. Keep your pour moving in slow concentric circles rather than holding it in one spot.
Finish adding all your water by about the 3:30 mark and allow the brew to finish dripping by 4 to 5 minutes total. If your brew takes much longer than that, the grind is probably too fine. If it drains too quickly, the grind is too coarse. Adjust accordingly next time.
5. Swirl, Serve, and Enjoy
Once the dripping stops, remove the filter and discard it. Swirl the Chemex gently to mix the layers evenly, then pour and enjoy immediately.
Brew Temperature by Roast Level
The Chemex's thick filter and slower flow rate accentuate acidity and sweetness. Adjusting water temperature helps balance those elements based on your roast.
| Roast Level | Water Temperature | Flavor Result |
|---|---|---|
| Light Roast | 200-205°F (93-96°C) | Bright, crisp cup with clean citrus or floral notes |
| Medium Roast | 195-200°F (90-93°C) | Balanced sweetness and round body |
| Dark Roast | 185-190°F (85-88°C) | Smooth, mellow cup with chocolate or caramel tones |
Fine-Tuning Your Brew
- Brew too slow: coarsen your grind slightly or pour more gently to maintain flow
- Coffee tastes sour: use hotter water or a finer grind
- Coffee tastes bitter: lower the water temperature slightly or coarsen the grind
- Coffee lacks sweetness: extend your bloom or increase total brew time by 15 to 20 seconds
A Note on Coffee Freshness
At I Have a Bean, every bag is roasted and shipped the same day you order. Fresh coffee releases more CO2, especially at the beginning of a brew, which creates a livelier bloom. If your beans are within three days of roasting, extend the bloom phase by an additional 20 to 30 seconds to let the coffee de-gas fully. You'll see the bed sink a bit when it's ready. That extra time helps unlock the full aroma, clarity, and sweetness of truly fresh coffee.
Whole bean coffee stays fresh for up to 21 days after the roast date when stored properly. For everything you need to know about keeping coffee at its best, see our guide on how to keep coffee fresh.
Pro Tip: Preventing a Stalled Chemex Brew
If your Chemex suddenly stops dripping mid-brew, the paper filter has likely collapsed against the glass spout, creating an airtight seal that stops water from flowing through the coffee bed. The fix is to gently lift one edge of the filter near the spout just enough to break the seal. The brew should resume immediately.
The better solution is to prevent it from happening in the first place. Insert a chopstick, straw, or thin spoon handle into the spout before you begin brewing to keep a small air gap open throughout the entire brew. This one small step eliminates the stall entirely.
Common Questions About the Chemex
Why are Chemex filters so thick?
The thicker filter removes oils and fine particles, which gives the coffee a remarkably clean taste and a smooth finish.
Can I reuse a Chemex filter?
It's not recommended. The paper fibers absorb oils from the previous brew, slowing flow rate and affecting cup clarity in subsequent brews.
What's the ideal grind for Chemex?
Medium-coarse, about the texture of coarse sand or kosher salt. Too fine and the brew will stall. Too coarse and the coffee will taste thin. See our full Coffee Grinding Guide for more detail.
Final Thoughts
The Chemex is timeless for a reason. Its thicker filter and elegant design make it easy to produce coffee that is both refined and full of character. When paired with freshly roasted beans, the results are clear, sweet, and deeply satisfying.
If you'd like to compare results across different pour-over styles, check out our Kalita Wave Brew Guide and Hario V60 Brew Guide, or start from the top with our Complete Guide to Pour-Over Coffee.
Browse our current lineup at ihaveabean.com. Every coffee is roasted to order, shipped the same day, and backed by our No-Risk, No-Hassle, Gonna Love It Guarantee.