Brewing Chemex Coffee for Two People

Quick answer

• Use a Chemex brewer and its specific paper filters.
• Aim for a 1:15 to 1:17 coffee-to-water ratio for two servings.
• Grind your beans to a medium-coarse consistency, like sea salt.
• Heat fresh, filtered water to around 200°F (93°C).
• Bloom the grounds for 30 seconds to release CO2.
• Pour slowly and steadily in concentric circles.
• Total brew time should be around 3.5 to 4.5 minutes.
• Clean your Chemex thoroughly after each use.

Who this is for

• Anyone looking to make a clean, bright cup of coffee with a Chemex.
• Folks who usually brew for one and want to scale up to two servings.
• Coffee lovers who appreciate a hands-on brewing experience.

What to check first

Brewer type and filter type

You’re using a Chemex, which is great. It’s a classic for a reason. Make sure you have the right filters for it. Chemex filters are thicker than most, and they really do make a difference in the clarity of your coffee. Don’t try to cheat with a different filter; it won’t fit right and might lead to a messy brew.

Water quality and temperature

This is huge. Bad water makes bad coffee, plain and simple. Use filtered water if your tap water isn’t top-notch. For temperature, you want it hot, but not boiling. Aim for 195°F to 205°F (90°C to 96°C). If you don’t have a thermometer, just let your boiling water sit for about 30 seconds before you pour.

Grind size and coffee freshness

Freshly ground coffee is king. Seriously, ditch the pre-ground stuff. For a Chemex, you want a grind that’s medium-coarse, kind of like coarse sand or sea salt. Too fine and you’ll get bitterness and slow drainage. Too coarse, and your coffee will be weak. Store your beans in an airtight container, away from light and heat.

Coffee-to-water ratio

For two people, a good starting point is a 1:15 to 1:17 ratio. This means for every gram of coffee, you use 15 to 17 grams of water. Let’s say you want about 16 oz of coffee total (that’s roughly two mugs). That’s about 473 grams of water. So, you’d use around 28 to 31 grams of coffee (473 / 17 = ~28, 473 / 15 = ~31). Play around with this to find your sweet spot.

Cleanliness/descale status

A dirty brewer will ruin your coffee. Make sure your Chemex is sparkling clean. If you have hard water, you might need to descale your kettle periodically. Mineral buildup can affect water temperature and flow. A quick rinse of the Chemex and filter holder is usually enough after brewing.

Step-by-step (brew workflow)

1. Rinse the filter: Fold your Chemex filter into a cone and place it in the brewer. Pour hot water over the filter to rinse out any papery taste and preheat the brewer. Discard this rinse water.

• What “good” looks like: The filter is fully saturated, and the brewer is warm. No papery smell.
• Common mistake: Not rinsing the filter enough, leading to a papery taste. Avoid this by being thorough.

2. Add coffee grounds: Measure your desired amount of coffee (around 28-31 grams for 16 oz total liquid) and add it to the rinsed filter. Gently shake the brewer to level the coffee bed.

• What “good” looks like: An even bed of coffee grounds.
• Common mistake: Uneven grounds can lead to uneven extraction. Don’t just dump it in; level it out.

3. Tare your scale: Place the Chemex with the grounds on your scale and zero it out. This is crucial for accurate water measurement.

• What “good” looks like: Your scale reads 0.0 grams.
• Common mistake: Forgetting to tare. This throws off your entire ratio.

4. The bloom: Start your timer. Gently pour just enough hot water (around twice the weight of your coffee, so 56-62 grams) over the grounds, ensuring all are saturated. Wait 30 seconds.

• What “good” looks like: The coffee grounds puff up and bubble, releasing CO2.
• Common mistake: Pouring too much water or not waiting long enough. This step is vital for even extraction.

5. First pour: After the bloom, start pouring water in slow, concentric circles, moving from the center outwards, then back inwards. Avoid pouring directly down the sides of the filter. Aim to add about half of your total water (around 230-240 grams).

• What “good” looks like: A steady, controlled pour that keeps the water level consistent without overflowing.
• Common mistake: Pouring too fast or aggressively. This can agitate the grounds too much and create channels.

6. Second pour: Continue pouring in slow, circular motions, maintaining a steady flow. Add the remaining water gradually until you reach your target weight (around 473 grams total). Keep the water level below the top rim of the filter.

• What “good” looks like: The coffee bed is evenly saturated, and the water is draining at a good pace.
• Common mistake: Drowning the grounds or letting the water level get too high. This can lead to over-extraction.

7. Let it drain: Once you’ve added all the water, let the coffee finish dripping through the filter. The total brew time should be between 3.5 and 4.5 minutes.

• What “good” looks like: The coffee is mostly drained, leaving a relatively dry puck of grounds.
• Common mistake: The brew taking too long (over 5 minutes) or finishing too quickly (under 3 minutes). Adjust grind size next time.

8. Remove filter and serve: Once dripping stops, carefully remove the filter and discard the grounds. Swirl the Chemex gently to mix the coffee, then pour into your mugs.

• What “good” looks like: Clean, aromatic coffee ready to enjoy.
• Common mistake: Not swirling the Chemex. The coffee can stratify, leading to an uneven taste.

Common mistakes (and what happens if you ignore them)

Mistake	What it causes	Fix
Using stale beans	Flat, dull, uninspired coffee flavor	Buy fresh beans and grind them right before brewing.
Incorrect grind size	Too fine: bitter, slow drain. Too coarse: weak, fast drain.	Adjust your grinder to medium-coarse for Chemex.
Wrong water temperature	Too hot: bitter. Too cool: sour, weak.	Use water between 195-205°F (90-96°C).
Inconsistent pouring	Uneven extraction, channeling, off-flavors	Pour slowly and steadily in concentric circles.
Not preheating brewer/filter	Coffee cools too fast, affecting extraction	Rinse filter and brewer with hot water before adding grounds.
Over-extraction	Bitter, astringent, harsh taste	Reduce brew time, increase grind size, or use less coffee.
Under-extraction	Sour, weak, grassy taste	Reduce brew time, decrease grind size, or use more coffee.
Dirty equipment	Off-flavors, metallic taste, stale coffee	Clean your Chemex and kettle thoroughly after each use.
Using tap water	Off-flavors, mineral buildup, inconsistent taste	Use filtered or bottled water for a cleaner cup.
Rushing the bloom	Incomplete CO2 release, uneven extraction	Wait the full 30 seconds after the initial pour.

Decision rules (simple if/then)

• If your coffee tastes bitter, then decrease your grind size slightly for the next brew because finer grinds extract more flavor.
• If your coffee tastes weak and sour, then increase your coffee-to-water ratio (use more coffee) because you might not be using enough grounds.
• If the brew time is too fast (under 3 minutes), then grind your coffee finer because a finer grind slows down the water flow.
• If the brew time is too slow (over 5 minutes), then grind your coffee coarser because a coarser grind speeds up the water flow.
• If you notice dry spots in the coffee bed after brewing, then pour more evenly and ensure all grounds are saturated during the pour.
• If your coffee has a papery taste, then make sure you rinsed your filter thoroughly with hot water before brewing.
• If your coffee tastes muddy or silty, then check your filter seating and ensure you’re using the correct Chemex filters.
• If your coffee tastes dull even after brewing correctly, then check the freshness of your beans and consider grinding them right before you brew.
• If your water tastes off, then use filtered water for brewing because water quality significantly impacts coffee flavor.
• If you want a stronger cup, then increase your coffee dose while keeping the water amount the same, following your desired ratio.
• If you want a lighter cup, then decrease your coffee dose or increase the water amount.

FAQ

How much coffee should I use for two people?

For two average mugs (around 16 oz total liquid), start with about 28-31 grams of coffee. This is roughly 4-5 tablespoons, but weighing is always more accurate.

What is the ideal water temperature for Chemex?

Aim for water between 195°F and 205°F (90°C to 96°C). If you don’t have a thermometer, let boiling water sit for about 30 seconds before pouring.

Can I use a regular coffee filter in my Chemex?

No, Chemex uses its own specific, thicker paper filters. They are designed to trap more oils and sediment, giving you a cleaner cup. Using a different filter won’t work well.

My coffee is draining too slowly. What’s wrong?

This usually means your grind is too fine. Try a coarser grind next time. Also, ensure you’re not pouring too aggressively, which can clog the filter.

How long should the entire brewing process take?

The total brew time, from the start of the bloom to the last drip, should be between 3.5 and 4.5 minutes for a Chemex brew for two.

What if I don’t have a scale?

While a scale is highly recommended for consistency, you can use measuring spoons and cups. For two people, start with about 4-5 level tablespoons of whole beans, grind them, and then use about 3 cups of water. Adjust to taste.

Why does my coffee taste bitter?

Bitterness often comes from over-extraction. This could be due to a grind that’s too fine, water that’s too hot, or brewing for too long. Try adjusting one variable at a time.

How do I clean my Chemex?

After brewing, discard the filter and grounds. Rinse the Chemex thoroughly with hot water. For a deeper clean, you can use a specialized coffee brewer cleaner or a mixture of baking soda and water.

What this page does NOT cover (and where to go next)

• Specific coffee bean recommendations for Chemex.
• Detailed explanations of extraction theory (TDS, extraction yield).
• Comparisons to other brewing methods like V60 or Kalita Wave.
• Advanced techniques like pulse pouring or specific agitation methods.