A pour-over method using an hourglass-shaped glass vessel and a thick, proprietary paper filter, producing an exceptionally clean, tea-like cup by removing more oils and fine particles than a standard cone filter.
Coffee-to-water ratio
55–65 g per litre (typically 60)
Grind
Medium-coarse.
Water temperature, as commonly used
90-96 celsius (typically 94)°C
Contact time
210-300 seconds (typically 240)
Skill level
intermediate
Descriptive grind labels like this are illustrative starting points, not precise measurements — the same label can mean different particle sizes on different grinders. See the grind size guide for how to dial this in on your own equipment.
In short
A Chemex is a one-piece glass brewer shaped like an hourglass: coffee and a folded paper filter sit in the top half, and the brewed coffee collects in the bottom half, which doubles as the serving carafe. It is a pour-over, so you make it by pouring hot water over the grounds by hand.
The glass is the famous part, but the filter is what you taste. Chemex paper is markedly thicker than ordinary cone filters, and nearly everything that makes this brewer different, including the very clean cup, the light body and the slow drain, follows from that one fact.
The filter is the brewer
CoffeeHQ explanation
Paper filters hold back two things that a metal mesh lets through: the finest particles of ground coffee, and most of the coffee's oils. A thicker, denser paper holds back more of both. With less oil and almost no suspended sediment, the liquid feels lighter in the mouth and individual flavours are easier to tell apart, which is why Chemex coffee is so often described as tea-like.
The same density slows the water down. In a V60 the paper offers little resistance and the coffee bed sets the pace; in a Chemex the paper itself is a real restriction. That is why the usual advice is to grind a step coarser than you would for a cone dripper. If you carry a V60 grind straight over, the brew runs long and can turn bitter.
The trade is body for clarity. A coffee you enjoy for its syrupy weight in a French press will taste thinner here, and that is the brewer working as designed, not a fault to correct.
Where to start with a Chemex
Typical range
Thirty grams of coffee to 500 grams of water makes two generous cups and suits the common six-cup model.
Where to start with a Chemex
Variable
Typical range
What moving it does
Coffee to water
About 55–65 g per litre (roughly 1:15 to 1:18)
A touch weaker than many V60 recipes is common, because the cup is prized for delicacy.
Grind
Medium-coarse, coarser than for a cone dripper
Compensates for the resistance of the paper.
Water temperature
About 90–96 °C
The large glass vessel loses heat quickly, so err towards the top for light roasts.
Bloom
About twice the coffee's weight, for 30–45 seconds
Total brew time
About 3½–5 minutes
Longer than most single-cup pour-overs, mainly because batches are larger and the paper is slower.
These are conventional starting points for a medium batch. A single small cup in a large Chemex behaves differently, because a shallow bed drains faster and extracts less.
Folding, seating and pouring
Widely documented
Put the thick side against the spout. A folded Chemex filter has three layers on one side and one on the other. The three-layer side goes against the pouring channel, where it keeps the paper from collapsing into the spout and sealing it.
Rinse generously. There is a lot of paper here. Pour plenty of hot water through it, both to remove any papery taste and to warm the glass, then tip the rinse water out through the spout without disturbing the filter.
Bloom, then pour in stages. Wet all the grounds, wait for the bubbling to slow, then add the rest in a few steady circular pours, keeping the water level well below the rim of the paper.
Lift the filter out when the stream thins to a drip. Waiting for the very last drops adds brewing time without adding much that tastes good. Remove the filter, swirl the carafe and serve.
When a Chemex goes wrong
CoffeeHQ explanation
The brew stalls and takes far longer than five minutes
Usually because: The grind is too fine for this paper, or the filter has sealed against the spout so that air cannot escape from the lower chamber.
Change first: Grind coarser first. If it still stalls, check the filter's thick side is against the spout.
V60 — Thinner paper and a faster, more adjustable flow. Usually a little more body and more sensitivity to how you pour.
Kalita Wave — A flat bed and restricted drain make it more even and more forgiving, with a rounder cup than the Chemex's very light one.
French press — The opposite end of the filtration scale: a metal mesh that keeps the oils and fines the Chemex removes.
One comparison worth making
CoffeeHQ explanation
Same coffee, two filters
Change
Brew the same coffee in a Chemex and in any thinner-paper dripper or a French press.
Keep the same
The coffee, the ratio, the water and its temperature.
What to notice
Compare how heavy each feels in the mouth and how easily you can pick out separate flavours. That difference is filtration, more than anything about the brewers' shapes.
What to do next
Dialling in filter coffee — the order to work in, what each control does, and why a Chemex is read against its own last brew.
Plan the pours — Turns a dose and ratio into bloom and pour targets you can follow on a scale.
Compare brewing methods — Shows where the Chemex sits on body, clarity and effort beside up to four others.
Become a barista — A structured programme from dose and grind through milk, drinks and maintenance.
Owning a Chemex: the filter, the pour and the glass
A Chemex is a brewer and a server in one piece of glass, and nearly everything particular to it comes from its paper. This part covers what each feature is for, how to set up a new one, where the filter goes and why, what each change tends to do, and how to look after the glass and the collar.
Your maker's instructions come first. The maker's own support pages are short and specific, and where a line below is marked as the maker's it comes from them. They cover the classic glass coffeemakers with a wood collar; glass-handled and other versions have their own instructions.
I have just bought one. What do I do first?
Find the spout and the channel. The groove that runs from the top of the brewer down to the waist is both the pouring spout and the way air leaves the lower chamber while coffee drips in. Everything about placing the filter follows from keeping it open.
Take off the collar and tie, and wash the glass. The maker's instruction is to remove the wood collar and the tie before washing, then swirl warm soapy water in the carafe and rinse. Put the collar back on dry.
Open the filter with three layers on one side. A folded filter opens into a cone that has one layer on one side and three on the other. The maker's instruction is that the thick three-layer side covers the pouring spout.
Rinse the paper and pour the water away. The maker's answers page says this is not a required step, and that it may be done to rinse away any paper fibres and to heat the carafe, with the water poured away before brewing. Pour it out through the spout with the filter held in place.
Weigh a starting recipe. The maker's own measure is one rounded tablespoon of medium-coarse coffee for each five-ounce cup. To make that repeatable, weigh what your tablespoon holds once and use the weight from then on; the recipe section above gives a range in grams.
Wet the grounds, wait, then pour slowly. The maker's steps: bring water to the boil and take it off the heat until it stops boiling hard, pour a little in circles to wet the grounds, wait about thirty seconds, then pour the rest slowly, keeping the level below the top of the brewer.
Lift the filter out and taste. When the dripping has slowed to nothing, lift the filter and grounds out. Note how long it took and how the cup tastes, and change one thing next time.
What each part of a Chemex is for
The upper cone
Holds the filter and the coffee. It has smooth walls and no ribs, so the wet paper lies against the glass everywhere except at the channel.
The pouring spout and air channel
A groove in the upper cone. Coffee is poured out through it, and while brewing it is the only way air can leave the lower chamber. If the paper seals across it, the air has nowhere to go and the brew slows or stops.
The bonded filter
A heavy paper, folded so that one side of the cone is three layers thick. It does most of the filtering and a good part of the slowing, which is why a Chemex is said to be a brewer made by its paper.The maker gives no figure for how much thicker its paper is, so none is given here.
The collar and tie
On the classic models, two pieces of wood held by a leather tie form the handle, so the hot glass can be picked up. They come off for washing.
The lower chamber
The server. The maker describes the glass as borosilicate. The maker says the small glass bump on the front marks the halfway point on the larger sizes and the full line on the three-cup brewer; treat it as a guide and weigh the water.
Why the thick side of the filter goes over the spout
Maker's instructions
The maker's instruction is that the three-layer side of the filter covers the pouring spout. Its stated reason, on its answers page, is that the paper should not collapse into the air channel.
The mechanism is simple. As coffee fills the lower chamber, the air in it has to get out, and the channel is the way out. A single wet layer of paper is soft enough to be drawn into the groove and seal it. Three layers are stiffer and bridge it. If the brew slows to a stop with water still above the coffee, lifting the edge of the filter at the spout for a moment usually lets the air out and the flow restart.
That is an explanation of airflow. It is not a claim that the orientation changes how the coffee extracts.
The filters, and what is known about them
Maker's instructions
The maker lists six filters: pre-folded circles, pre-folded squares, pre-folded natural squares, unfolded half-moons, unfolded natural half-moons and unfolded circles. The maker says some people like the points of the squares for lifting the filter out. Natural is the brown paper: the maker says the white paper goes through an oxygen cleansing bath and hot water baths, the brown through the hot water baths only, and that it uses no bleach in either.
The maker's answers page says the three-cup brewer takes a different, unfolded filter from the larger sizes. Beyond that, the maker's answers page says all of its filters function in the same way and that the choice is a matter of preference, and it gives no dimensions. CoffeeHQ has nothing to set beside that. If you change filter type, check the grind again.
What changes what in a Chemex
Each line is a tendency and the mechanism behind it, not a promise about taste. The last part of each says what else the result depends on.
Grindfiner or coarser
Finer slows the drawdown and takes more from the coffee; coarser does the reverse. Because the paper already slows the water, a Chemex is usually ground coarser than a V60 for the same brew.
But it also depends on: The grinder's share of very fine particles, which the heavy paper catches and which then slow it further.
Dose and ratiomore coffee or more water
More coffee for the same water gives a stronger cup and a deeper bed, which drains more slowly.
But it also depends on: The size of the brewer. The same recipe behaves differently in a three-cup and an eight-cup.
Batch sizea small brew or a full one
A large batch has a deep bed and takes much longer to drain at the same grind, so large batches are commonly ground coarser. A very small batch in a large brewer gives a shallow bed that drains quickly.
But it also depends on: Whether the ratio was kept when the recipe was scaled. A weak large batch is often just a recipe that lost its ratio.
Pouringfaster and harder, or slower and gentler
A hard pour stirs the bed and sends fine particles to the paper, slowing the brew. A gentle pour disturbs it less. The maker asks for a slow pour in circles or back and forth.
But it also depends on: The kettle, and how full the cone is when you pour.
Agitationmore stirring, or less
Stirring evens out wetting and speeds up what the water takes. With this paper it also tends to lengthen the drawdown noticeably.
But it also depends on: The grind. A dusty grind and a stir together are the usual cause of a stall.
The filterwhich paper, and how it sits
The paper is a large part of the resistance. A different type, or the same type seated differently against the channel, can change the drawdown at the same grind.
But it also depends on: Whether the air channel stays open. A sealed channel looks like a grind problem and is not one.
Water temperaturehotter or cooler
Hotter water generally dissolves more, more quickly. The maker's instruction is water taken off the boil and allowed to settle.
But it also depends on: The glass, which takes heat from the first pour unless it was rinsed with hot water first.
When a Chemex goes wrong
For each thing you might notice: what to consider, since there is rarely one cause, and the first thing to try. One change, then brew again.
The drawdown stalls
Consider
The paper has sealed across the air channel
A lot of very fine particles on the paper
A grind too fine for the size of the batch
Heavy stirring or a hard pour
Try first: While it is stalled, lift the edge of the filter at the spout. If the flow restarts it was air, and the filter needs reseating with its three-layer side over the spout. If not, grind a clear step coarser next time.
A recipe that was scaled up without keeping the ratio
A tablespoon measure, which varies with the coffee and the grind
A brew that took little from the coffee: thin and also sharp
Try first: Weigh the coffee and the water once. If the ratio is where you meant it and the cup is balanced, use more coffee. If it is thin and sharp, grind finer and leave the amounts alone.
A strong brew: the dryness fades when a little water is added to the cup
A long, stalled drawdown
Uneven wetting in a deep bed
The coffee, or the water
Try first: Do the water test on the cup you have. If the dryness fades, use a little less coffee. If the brew also stalled, deal with the stall first and taste again.
The paper tore, or folded over at the rim and let grounds past
Grounds were knocked in when the filter was lifted out
A different, lighter filter than the brewer is meant for
Try first: This paper holds back more than most, so sediment is nearly always mechanical. Look at the used filter for a tear, and lift it out slowly.
Change one thing, observe, learn
Each of these changes one thing and holds the rest. Brew the two side by side where you can, and write down what you notice before deciding which you prefer.
The filter both ways round
Change
Brew once with the three-layer side over the spout and once with the single-layer side there.
Keep the same
The coffee, the grind, the amounts and the pour.
What to notice
Whether the second brew slows or stops with water still above the bed. This shows what the instruction is for.
Two grinds, one batch size
Change
Brew at your usual setting and at a clear step coarser.
Keep the same
The coffee, the amounts, the filter and the pour.
What to notice
How much the drawdown shortens, and whether the cup becomes cleaner or simply thinner.
A small batch against a full one
Change
Brew half your usual recipe, then the full recipe, at the same ratio and grind.
Keep the same
The ratio, the grind and how you pour.
What to notice
The difference in drawdown, and which tastes fuller. This is why a recipe cannot simply be doubled.
What to avoid with a Chemex
Seating the filter with its single-layer side against the spout. The maker's instruction is the thick side over the spout, so the paper does not collapse into the air channel.Maker's instructions: Chemex Corporation
Filling to the brim. The maker asks for the water level to be kept well below the top of the brewer.Maker's instructions: Chemex Corporation
Reheating coffee in the brewer in a microwave. The maker says none of its products should be reheated in a microwave.Maker's instructions: Chemex Corporation
Putting it in a dishwasher with the collar and tie on, or loose among other dishes. The maker allows a dishwasher only with both removed and the carafe secured so that it cannot knock against anything.Maker's instructions: Chemex Corporation
Carrying a full brewer by the glass. It holds hot coffee above your hand; lift it by the collar or the handle, and check the tie is tight before each use.CoffeeHQ reasoning
Heating it on a hob in any way the maker does not describe. Its answers page allows keeping coffee warm on a low gas flame or directly on a glass-top hob at a low temperature, and on an electric coil only on the wire grid it sells, on a low setting. Follow the leaflet for your own model.Maker's instructions: Chemex Corporation
Looking after the glass and the collar
Every time
Lift out the filter and grounds, then swirl warm soapy water in the carafe and rinse.Maker's instructions: Chemex Corporation
Rinse soon after use. Coffee oil dries onto the narrow waist, where a hand cannot reach, and is much harder to shift later.Common practice
From time to time
Remove the collar and tie and wash the glass by hand, or in a dishwasher once they are off and the carafe is secured.Maker's instructions: Chemex Corporation
For a brown film in the waist, a long-handled bottle brush is the usual tool. Keep the wood and the leather dry and put them back on only when the glass is dry.Common practice
Parts that wear
The leather tie
It stretches and dries out with use. A collar that slips on the glass means the tie needs retying or replacing before the brewer is carried full.CoffeeHQ reasoning
The wood collar
Water darkens and cracks it over time, which is why it comes off for washing.Common practice
The glass
A chip or a crack anywhere is a reason to stop using it: the brewer is filled with near-boiling water and carried by its neck.CoffeeHQ reasoning
What else changes how it is used
Only the things that change the brewing. None of this is a list of things to buy.
The maker's own filters
The brewer is designed around its heavy paper. A lighter paper drains differently and may not bridge the air channel.
A scale
The maker measures in tablespoons and cups. A scale turns that into something you can repeat and scale up.
A narrow-spouted kettle
A wide cone and a deep bed reward a pour you can place and slow down.
A bottle brush
The waist is too narrow for a hand, and it is where the film builds.
From the first brew to knowing it well
Seat the filter the same way every time. Three layers over the spout, not pushed into the groove. Until this is habit, stalls will look like grind problems.
Move from tablespoons to grams. Weigh the coffee and the water, and write down one recipe you can repeat.
Find the grind for your usual batch. One step at a time, reading the drawdown and tasting. Expect it to be coarser than for a small cone.
Learn what batch size does. Brew a small and a full batch at one ratio, and note how the grind has to move to keep the cup the same.
Refine the pour. Fewer, gentler pours for a cleaner drawdown; then decide by taste whether you prefer it.
Improve this, from here
Make my coffee better: Chemex — What you noticed, the possibilities, the quickest check and one change, with what this brewer's shape adds.
Brew recipe scaler — A Chemex is often used for large batches, and this keeps the ratio when you scale.
Extraction basics — Why a weak cup and an unbalanced one are different problems.
How this method is usually described
Produces an unusually clean, light-bodied, tea-like cup — the thick proprietary filter removes more oils and fine particles than a standard cone filter, trading some body and sweetness for extra clarity and brightness.
A description of the usual expectation, not a measured result. The coffee, its roast, the water and how it is brewed change the cup at least as much as the brewer does.
Derived from CoffeeHQ's own Change the Taste guidance for this method, not a marketing feature list.
Grind size
Pouring pattern
Water temperature
Agitation
Dose
Filter
Water amount
Change the taste
Chemex is a pour-over dripper close enough to V60 that the same grind, pour and temperature guidance applies.
Tastes sour
(Chemex)
The brew tastes sour or thin, and often drains through faster than your usual brews. Flow and taste agree here: the water took little from the coffee.
Try the first step below on its own, taste, then move to the next one only if needed.
Change
Try
Why
Watch for
FirstGrind size
Decrease: a small step finer
Slows the drawdown and usually increases extraction.
—
Pouring pattern
Check / reset: pour more slowly and evenly across the whole bed
Even saturation extracts more consistently than fast, off-centre pouring.
Very slow pouring can itself stall the brew if the grind is already fine.
Water temperature
Increase: a few degrees hotter
Hotter water extracts more quickly, within the method's normal range.
—
Agitation
Increase: ensure a full, even bloom before the main pours
A poorly saturated bloom leaves parts of the bed under-extracted.
—
Check for channelling first (water finding a fast path through the bed) — that can taste sour even with a correct grind, and the fix is even pouring, not a finer grind.
When to reset: Return to your usual grind and pour pattern before making a second change.
The brew tastes bitter or dry, often alongside a slow, stalling drawdown. Flow and taste agree here: the water stayed long and took a great deal. A strong brew can taste the same, so try a little water in the cup first.
Try the first step below on its own, taste, then move to the next one only if needed.
Change
Try
Why
Watch for
FirstGrind size
Increase: a small step coarser
Speeds up the drawdown and usually reduces extraction.
—
Dose
Decrease: a gram or two less coffee for the same water, or a splash of hot water in the cup
Makes the cup a little weaker. In the one panel study CoffeeHQ has read, bitterness rose with strength and showed no clear link to extraction, so this is worth trying before or beside the grinder.
Go too far and the cup turns thin.
Agitation
Decrease: pour more gently, avoid stirring the bed
Less turbulence reduces the chance of over-extracting fines.
—
Filter
Check / reset: check the filter isn't clogging
A slow drain can be a blocked filter or too many fines rather than a grind problem.
—
Water temperature
Decrease: a few degrees cooler, especially for darker roasts
Slower extraction can soften bitterness.
—
When to reset: Check the grinder for excess fines before assuming the recipe alone is the cause.
Each step links to its own page; this is the order they belong in.
I have coffee and a brewer
You own something to brew with and want a good cup from it.
Find your brewer's page, start from its recipe, and change one thing at a time. The later steps are for when the cup is not right, and for finding out why a change worked.
1Find your brewerWhat it does to the coffee, and a starting recipe labelled as a starting point.
2Work out the amountsCoffee and water for the cup you are making; the recipe scaler follows from it.
3If the cup is not rightChoose the brewer, tick what you noticed: the quickest check, and one change.
4One change per brewThe same loop written out for filter coffee, from the first brew to a recipe you keep.
5Why the change worksStrength and extraction as two numbers, and what a taste can and cannot tell you.
6Test it yourselfHow to compare two cups so the difference is the thing you changed.