Chemex Coffee: Why the Thick Filter Produces a Different Cup than V60

The Chemex is one of the most distinctive pour-over brewers, and the thick bonded paper filter it uses produces a fundamentally different cup than the V60 or other cone drippers. The filter is approximately 20 to 30 times heavier than a standard V60 filter, and this thickness removes substantially more of the coffee oils and fine sediment that pass through thinner filters. The result is a cup that is noticeably cleaner, brighter and lighter-bodied — often described as "tea-like" — with more pronounced acidity and less of the heavy, syrupy body that thinner-filter brewers produce.

The Chemex is not just about the filter, though. The thicker filter slows drawdown significantly, which means the brew time is longer (typically 4 to 6 minutes) and the brewing dynamics differ from a V60 or Kalita. Understanding these differences is essential to brewing Chemex well, because the recipes that work for a V60 do not transfer directly.

The principle behind Chemex coffee

Chemex's distinctive cup comes from the thick bonded paper filter, which removes most oils and fine sediment. The filter also slows drawdown, which means the coffee is in contact with water longer. The combination of more thorough filtration and longer brew time produces a cup that is clean, bright, tea-like and lighter-bodied than other pour-over methods. The brewer is excellent for highlighting delicate, floral, acidic coffees; less suitable for full-bodied, chocolatey coffees that benefit from more oil and sediment.

Three things are easy to confuse here, and separating them saves a lot of wasted coffee. Strength is how concentrated the cup is. Extraction is how much the water pulled out of the grounds. Preference is whether you like the result. A stronger cup is not a better-extracted one, and the recipe a cafe uses is not automatically the recipe your grinder wants.

What most changes the result

Filter weight

The Chemex bonded filter is approximately 100–110 grams per filter, compared to 2–4 grams for a V60 filter. The thickness removes more oils (which produce body) and more fine sediment (which produces texture), producing a cleaner cup.

Brew ratio

A standard Chemex ratio is 1:16 (60 grams coffee per litre water). Slightly higher ratios (1:15) produce a more concentrated cup; lower ratios (1:17) produce a thinner cup. The Chemex lends itself to ratios that emphasise clarity.

Grind size

Medium-coarse is standard for Chemex. A grind that is too fine produces an excessively slow drawdown and over-extraction; a grind that is too coarse produces a thin, under-extracted cup.

Bloom and pouring

A 30–45 second bloom allows CO₂ to escape before the main pour. Subsequent pours should be slow and even, keeping the bed level. The total brew time of 4–6 minutes is a useful guide but not a rigid target.

Coffee selection

Light-to-medium roasted, washed, delicate coffees (Ethiopian, Kenyan, Colombian washed) are particularly suited to Chemex. Full-bodied, dark-roasted coffees lose some of their appeal through the thick filter.

A repeatable starting method

1. Use a Chemex bonded filter. Pre-wet the filter thoroughly with hot water, then discard the water. Pre-wetting removes paper taste and warms the brewer.
2. Add a measured dose of coffee to the rinsed filter. Use 30–40 grams for a 600 ml Chemex (standard half-size).
3. Pour a bloom of 60–80 ml at 93 °C and wait 30–45 seconds. The bloom should be even across the bed.
4. Pour the remaining water in two or three stages, keeping the bed level and avoiding the filter sides.
5. Allow total brew time of 4–6 minutes. The drawdown should slow but complete. Serve immediately or keep warm in a thermos.

Write down the dose, the water weight, the temperature and the total time, then one honest word for the cup. "Sour", "dry", "thin" and "heavy" are all useful when they describe a specific brew. Change one number and run it again.

The numbers we use

These are the figures behind our own pour-over cone guidance, and the starting point this article assumes.

When it goes wrong

• Sour or thin — Under-extracted — water passed through too fast Grind a little finer, or pour more slowly.
• Bitter or harsh — Over-extracted — water sat too long Grind a little coarser, or use slightly cooler water.
• It drained very slowly — Grind too fine, or the bed was disturbed Go coarser and avoid pouring hard on to one spot.

Common mistakes

• Using a V60 grind setting for Chemex. The thick filter requires a coarser grind.
• Brewing dark-roasted coffees through Chemex. The thick filter removes much of the body that makes dark roasts appealing.
• Treating the recipe as fixed. Coffee, grind, water temperature and pouring pattern all interact; taste and adjust.
• Letting the drawdown exceed 7 minutes. Extended contact time produces over-extraction, regardless of the recipe.

How to choose your next adjustment

Use Chemex when you want a clean, bright, tea-like cup that highlights delicate, acidic, floral coffees. Brew with a medium-coarse grind, 1:16 ratio, 93 °C water and a 4–6 minute total brew time. The thick filter is a tool for clarity; use it deliberately.

One caveat on caffeine: brewing method and roast colour tell you very little about the dose. A large cold brew can carry several times what a single espresso does. Use the figure for the specific product rather than for the category.

Related on CupCura

• The brewing guide and timer
• The equipment guide

Frequently asked questions

What should I change first with chemex coffee?

Filter weight. The Chemex bonded filter is approximately 100–110 grams per filter, compared to 2–4 grams for a V60 filter. The thickness removes more oils (which produce body) and more fine sediment (which produces texture), producing a cleaner cup.

What is the most common mistake?

Using a V60 grind setting for Chemex. The thick filter requires a coarser grind. It is worth ruling that out before changing anything else, because it makes every other adjustment harder to read.

Does coffee selection matter?

Light-to-medium roasted, washed, delicate coffees (Ethiopian, Kenyan, Colombian washed) are particularly suited to Chemex. Full-bodied, dark-roasted coffees lose some of their appeal through the thick filter.

How many brews before I judge a coffee?

Two or three. One uneven bed or a mistimed pour can misrepresent a good roast, and three careful attempts is enough evidence that it simply is not to your taste.

Sources

• Specialty Coffee Association brewing standards — Chemex brewing control variables; Folmer B. The Craft and Science of Coffee. Academic Press, 2017 — filter material effects on extraction.