The Kalita Wave
A flat bottom pierced with three small holes and a wavy paper filter that barely touches the wall: the Kalita Wave spreads the coffee into a shallow bed. It is the flat-bottom answer to the V60 cone, for a more even extraction from one layer to the next.
What does a flat bottom change compared with a cone?
Start the scene or choose a stage. The animation simplifies the mechanism; what follows gives the details and the available references.
The same dose of coffee spreads over a flat bottom instead of piling up in a point. The layer of grounds is less thick.
Read the stages without animation
- A spread-out bedThe same dose of coffee spreads over a flat bottom instead of piling up in a point. The layer of grounds is less thick.
- The wavy filterThe waves of the paper hold it away from the wall. Little water passes between the paper and the glass.
- Three small holesWater accumulates above the bed and drains through three narrow holes. The flow depends less on the hand that pours.
- The paper sagsIf the filter lies down over the holes, the water passes through only a small zone. The bed clogs and the flow slows; gently lifting the filter is often enough to restart it.
- A more even extractionWhen the paper stays lifted, the water passes through all the layers about equally. The cup gains in softness.
To remember: The flat bottom spreads the bed; as long as the paper stays lifted, the water passes through all the layers about equally.
In history: Around 2010 according to retailers, at a Japanese maker founded in 1958 in Tokyo.
Read the full article and its sources ↓History
Kalita is a Japanese company. Its history, as its site displayed it in 2014, has it born in October 1958 in Nihonbashi, Tokyo, and becoming a joint-stock company in July 1959; it also notes the launch of an unbleached filter paper in 1991 and of a bagasse paper, made of sugarcane fiber, in 1995 (source 1). This same history does not mention the Wave.
The date of 2010 comes only from retailers, which plate XV repeats. No Wave patent was found, although a retailer speaks of a “patented” filter (source 3). The file remains open: the Japanese patent database would be needed to close it.
The idea, though, is old. In 1917, Aborn, rapporteur of the American roasters, already held that the common error of the filter was being too narrow: the layer of grounds becomes too thick, the water lingers, cools, and the contact lengthens more than it should (source 2). A wide flat bottom answers this reproach by spreading the same dose over a larger surface.
The two geometries have divided the manual filter between them. The cone passes more water near the top of the bed and sacrifices evenness of extraction in depth; the flat bottom extracts more evenly but has less free paper per gram of coffee (source 4). The ribs on the bottom of the Kalita are there to lift the filter above the holes (source 4).
The motion
The wavy filter is placed in the dripper without folding; its twenty waves, according to the retailer, hold it away from the wall (source 3). It is wetted, the grounds are poured in, the bed is leveled, then water is poured in several stages, keeping the bed covered. The retailer lists two sizes, 155 for one or two cups, 185 for more (source 3).
The knack lies in watching the bottom. If the paper sags onto the three holes, the water passes through only a tiny surface and the bed clogs; gently lifting the filter is often enough to restart the flow (source 4).
The settings
- Grindnot documented by the manufacturer in the pages found
- Dose1 to 2 tablespoons for 35 to 47 cl according to a retailer, for the 155 model (source 3)
- Brew rationot documented by the manufacturer; Gagné compares flat bottom and cone at 1:17 (source 4)
- Temperaturenot documented by the manufacturer; Gagné aims for a coffee slurry at 88 °C in his comparisons (source 4)
- Timenot documented by the manufacturer
- Pressurenone: gravity alone
What it has going for it
- The flat bed is shallower than a cone, and the water passes through it more evenly from one layer to the next (source 4).
- The wavy filter barely touches the wall, which reduces bypass compared with a ribbed cone, without eliminating it (sources 3 and 4).
- The three small holes hold the water in the dripper, which should make the result less dependent on pouring speed than with a single large hole; this is a deduction from the mechanism, not a measurement.
What is held against it
- The thin paper can sag onto the three holes; the water then passes through only a small zone and the bed clogs, a flaw that Gagné calls “infamous” with Kalita (source 5).
- The brand's wavy filters are required, and they crumple easily.
- The flat bottom offers less free paper per gram of coffee than a cone, which makes it more sensitive to fines (source 4).
What it gives in the cup
The Kalita Wave's paper stops sediment like the others. What sets it apart, according to Gagné, is consistency: the shallow bed receives a more evenly distributed water, and flat bottoms give him sweeter, less sour cups than the V60, which he attributes to a hotter slurry and a more even flow (source 4).
These comparisons concern another flat bottom, the Fellow Stagg [X], and the principle of the flat bottom; no published measurement of yield or concentration specific to the Kalita Wave was found.
Anecdotes
- Kalita distributed the American Fetco machines in Japan starting in 1993, one of the brands of batch filter coffee (source 1).
The sources for this sheet
- Kalita, “沿革” (company history), Internet Archive capture of 2014 (according to the manufacturer) · online · secondary
- William H. Ukers, All About Coffee, New York, 1922, ch. XXXVI (Aborn, Coffee Grinding and Brewing, 1917) · online · primary
- Seattle Coffee Gear, “Kalita Wave Glass Dripper, product guide” (retailer), accessed October 21, 2026 · online · secondary
- Jonathan Gagné, “Brewing with the Fellow Stagg [X] dripper,” Coffee ad Astra, December 9, 2020 · online · secondary
- Jonathan Gagné, “The four rules of optimal coffee percolation,” Coffee ad Astra, March 4, 2021 · online · secondary