01 — The brewer

How the Chemex works

The Chemex is a pour-over, like the V60 — you pour hot water over a bed of coffee in a paper filter and let gravity draw it through. What makes it different is the design and, above all, the paper. Invented in 1941 by the chemist Peter Schlumbohm, it is a single piece of borosilicate glass, its top a funnel and its base a carafe, joined at the waist by a wooden collar and a leather tie. It sits in the permanent collection of the Museum of Modern Art, and it still looks it.

The filter is the secret. Chemex papers are up to thirty percent thicker than an ordinary filter and bonded into a sturdy cone. That heavy paper traps not just the grounds but most of the oils and the very finest particles, so the coffee that reaches the carafe is exceptionally clean — bright, clear, aromatic and light in body, with none of the sediment of a press and even less of the texture of a V60. The trade-off is speed: all that paper slows the flow, so a Chemex likes a slightly coarser grind than a V60, or it will clog and stall.

Why people love it

Beauty is a large part of it — few objects on a kitchen counter look as good — but the cup earns its place too. The Chemex gives the cleanest, most delicate brew of any common method, which makes it a wonderful way to show off a bright, floral, expensive coffee. It brews several cups at once in a single elegant vessel, with no separate dripper and jug to juggle, and the finished carafe pours and serves beautifully. The downsides are few: the proprietary filters cost more and have to be bought, the glass is breakable, and that clean, light body is not for anyone who wants a rich, heavy cup — for that, reach for a press.

02 — Kit & recipe

The kit that matters

Because the Chemex is a pour-over, the kit is much the same as for a V60 — with one thing that is not negotiable:

• The Chemex and its bonded filters — the thick papers are the whole point, so use the real Chemex filters, folded into a cone with the three-layer side against the spout. An ordinary filter will not fit or brew the same.
• A burr grinder that grinds a consistent, medium-coarse grind. Consistency matters even more here, because the fines that a poor grinder makes are exactly what choke the heavy paper.
• A scale and a gooseneck kettle — to brew by weight and to place the water slowly and precisely, as with any pour-over.
• Good water and fresh beans, as always.

A recipe to start from

Grind a notch coarser than you would for a V60 — medium-coarse — so the water can move through the heavy paper. The classic six-cup Chemex is happy with these amounts, and you keep the same ratio as you scale up.

03 — Into the cup

Brewing it, step by step

The rhythm is the same as any pour-over — rinse, bloom, pour in stages — with two Chemex-specific habits: rinse the thick filter really well, and keep your pours gentle so the bed does not clog.

1. Boil the kettle. Open a filter into a cone with the three-layer side against the spout, and drop it into the top of the Chemex.
2. Rinse the filter thoroughly with hot water — more than you would think, because the heavy paper holds a papery taste — then tip the rinse water out of the carafe.
3. Add 30 g of coffee ground medium-coarse, level the bed, set the Chemex on the scale and zero it.
4. Bloom: pour to about 60 g, enough to wet all the grounds, and wait 45 seconds for the coffee to release its gas.
5. Pour in slow spirals, adding water in two or three stages up to 500 g, letting the level fall a little between pours and keeping the water off the paper.
6. Let it draw down fully — the whole brew should finish around four to four and a half minutes. Lift out the filter, give the carafe a gentle swirl, and serve.

If the brew is racing through in under three minutes, your grind is too coarse; if it stalls above five, it is too fine or you poured too hard. The thick paper is less forgiving of a fine grind than a V60, so when in doubt, err on the coarser side.

04 — Getting it right

Dialling it in

The Chemex responds to the same levers as any pour-over — grind, water temperature, ratio and pour — but grind carries even more weight here, because the thick filter punishes fines. Move the grind first, and only in small steps.

Fixing a cup that's not working

The Chemex has the two ordinary extraction faults, plus one that is unique to its thick filter — a stall. A sour, thin cup is under-extracted, so grind finer and use hotter water. A bitter, hollow cup is over-extracted, so grind coarser and pour more gently. And if the water pools on top and the brew crawls, the filter has clogged with fines: grind coarser and pour more softly so you do not drive the bed into the paper. Use the table below as a quick reference once you know what you are tasting.

Get the grind medium-coarse, pour gently, and the Chemex makes the most crystalline cup in coffee. It shows off a delicate, bright, high-grown single origin better than any other brewer — and the ones below are exactly that.