Clicks, burrs and dial numbers: what a grinder's specs actually tell you

In short

A grinder's spec sheet is three numbers — burr type, burr diameter and how many positions the dial has — and only one of them behaves the way buyers assume. Read across the whole catalogue, the spread in dial resolution dwarfs the spread in everything else.

A grinder is sold on three numbers: what shape its burrs are, how big they are, and how many positions the dial has. Across the 58 grinders charted here, those three numbers vary wildly — and the one that varies most is the one nobody reads.

The catalogue, split three ways

• Hand or motor. 36 hand grinders, 22 electric.
• Burr shape. 49 conical, 9 flat.
• Dial. 49 stepped, 9 stepless — a stepless grinder has no detents at all, so the "number of positions" question does not apply to it.
• Burr diameter. 38 mm to 83 mm, a spread of rather more than double.

A click is not a unit

Among the stepped grinders, the coarsest-resolution dial offers 9 positions across its whole range and the finest offers 405, about 45 times as many. Both are described as adjustable. They are not adjustable in the same sense.

This is the number that actually changes your morning, and it is the one buried at the bottom of the spec sheet. A dial with few positions moves a long way each click: you land either side of what you wanted and there is no setting in between. A dial with many positions lets you creep up on it, which matters enormously for espresso and barely at all for a french press.

So "how many clicks" is the wrong question, and "how much does one click move the grind" is the right one. Two grinders with a hundred positions each are not comparable if one spans espresso to french press over that hundred and the other spans espresso to filter. Every grinder page here publishes the range as well as the count for exactly that reason.

Hand or motor

Hand grinders outnumber electric ones here 36 to 22, which says more about what people buy than about what is better. A hand grinder puts its whole budget into burrs and a shaft; an electric one has to pay for a motor, a housing and a gearbox first. Pound for pound the hand grinder therefore arrives with better cutting edges, and at the lower end of the market the gap is not subtle.

What you buy back with a motor is time and repeatability — thirty seconds of arm work per dose sounds trivial until it is every morning, and a hand grinder's output depends slightly on how fast you turn it. The trade is real in both directions, and it is a trade about your kitchen rather than about the coffee. Neither shows up in a spec column.

Conical and flat

Conical burrs are 84% of the catalogue, which reflects the market rather than a verdict: nearly every hand grinder is conical because a cone is what fits in a tube you turn by hand.

The usual claim is that flat burrs produce a narrower spread of particle sizes and conical a wider one, and that the wider spread is what gives conical-ground espresso its reputation for body. There is something to it. It is also routinely overstated: burr alignment, how sharp the burrs still are, and how much old coffee the machine is holding onto all move the result more than the shape does, and none of the three appears on a spec sheet.

Burr size is not burr quality

Bigger burrs grind faster and run cooler, because the work is spread over more cutting edge and the beans spend less time inside. That is the honest case for diameter, and it is a case about throughput and heat rather than about the cup.

What bigger burrs do not automatically do is grind more evenly. A well-made small burr set beats a poorly aligned large one, and a hand grinder with 38 mm burrs will outperform plenty of larger electric machines on particle distribution while taking a minute of your arm to do it. Diameter is the easiest number to put on a box, which is why it ends up carrying more marketing weight than it has earned.

What the spec sheet leaves out

Three things, all of which matter more than any figure above. Alignment: whether the two burrs sit truly parallel, which varies between individual units of the same model. Retention: how much ground coffee stays inside between doses, staling and then joining your next brew. And the zero point, which is where the burrs first touch — it is set at the factory, it drifts, and it is why your grinder's number twelve is not necessarily anyone else's.

That last one is worth sitting with, because it undermines the whole idea of sharing settings. A published number for your exact model is a starting point offered in good faith by someone whose burrs are not your burrs. Use it to get close, then move one click at a time and taste. The specs choose the instrument; they do not play it.