Which to buy · Every setting
Niche Duo vs Rancilio Rocky
Two grinders cross-shopped at the same money. The Duo is numbered 0–50; the Rocky is numbered 0–55.
Which to buy
Choose the
Duo if you…
- single-dose — the hopper takes 60–70 g
- want separate espresso and filter burr sets you can swap without re-zeroing
- want stepless adjustment
Choose the
Rocky if you…
- are buying used — Rancilio no longer sells it new
- grind from a 0.3 kg hopper
- want stepped settings you can return to — up to 50 on the front ring
Shop links are affiliate links: BrewMark earns a commission if you buy through one, at no extra cost to you. The verdicts were written without regard to it.
Rancilio no longer lists the Rocky (its page now returns 404) and sells the Stile as its home grinder, so you'd be buying the Rocky used.
Sources: Niche — Duo user manual · Niche — Duo · Rancilio Group — Rocky (archived Jan 2022) · Rancilio Group — Rocky SD specifications (archived May 2022) · Rancilio Group — Stile
| Duo | Rocky | |
|---|---|---|
| Brand | Niche | Rancilio |
| Scale | Numbered dial | Numbered dial |
| Dial range | 0 – 50 | 0 – 55 |
| Burrs | Flat | Flat |
| Espresso → filter | 39.4 numbers | 20 numbers |
| Filter → coarse | 10.4 numbers | 23 numbers |
The same number means different things
Both grinders use a numbered dial, which makes it tempting to copy a number straight across. Setting 25 sits at grind index 25.1 on the Duo but 40 on the Rocky — far enough apart to change the cup.
Converting a setting
If a recipe quotes a setting for one of these grinders, read across for the equivalent on the other. Rows are spaced evenly by grind size, not by dial number — on a conical burr those are not the same thing.
| Duo | Rocky |
|---|---|
| 0.2 | 5 |
| 8.5 | 9 |
| 16.7 | 14 |
| 24.9 | 18 |
| 33.1 | 22 |
| 40 | 26 |
| 42.2 | 29 |
| 44.3 | 32 |
| 46.4 | 36 |
| 47.8 | 39 |
| 48.5 | 42 |
| 49.3 | 45 |
| 50 | 48 |
| Rocky | Duo |
|---|---|
| 5 | 0.2 |
| 9 | 8.5 |
| 14 | 16.7 |
| 18 | 24.9 |
| 22 | 33.1 |
| 26 | 40 |
| 29 | 42.2 |
| 32 | 44.3 |
| 36 | 46.4 |
| 39 | 47.8 |
| 42 | 48.5 |
| 45 | 49.3 |
| 48 | 50 |
Side by side, by brew method
Where each grinder lands for the same brew, worked out from its own dial curve.
| Method | Duo | Rocky |
|---|---|---|
| Espresso | 5.2 | 8 |
| Moka pot | 15.1 | 13 |
| AeroPress (short steep) | 24.9 | 18 |
| Pour over — V60 / cone | 37.6 | 24 |
| Siphon | 40.1 | 26 |
| Pour over — flat bottom | 40.9 | 27 |
| Steep and release — Clever / Switch | 41.7 | 28 |
| Drip / batch brew | 42.2 | 29 |
| Cupping | 42.7 | 30 |
| Chemex | 44.2 | 32 |
| French press | 47.5 | 38 |
| Cold brew | 48.9 | 44 |
The shape of each dial
Where the connectors bunch, that grinder’s dial is compressed and single steps count for more. Comparing the two shapes tells you which gives finer control, and where.
Niche Duo
Rancilio Rocky
Dialing in the Duo
The Duo extends the Niche single-dose concept to cover both espresso and brew properly, rather than stretching one dial across both. Like the Zero it is stepless, so treat the numbers below as targets to land near rather than detents.
Dialing in the Rocky
A stepped espresso grinder that has been the budget recommendation for a very long time. The 55 steps across 50mm flat burrs are its limitation — for espresso you will sometimes want a setting between two of them and there is not one, and a single step can move a shot by seconds. Twenty of those steps cover espresso through filter, which is more resolution than the fine end usually gets at this price. Two things make it an espresso grinder in practice rather than a general one: changing setting means holding the locking lever while twisting the hopper, and it keeps a couple of grams in the chute, so every switch between espresso and pour over costs you both fiddling and coffee. Most owners pick one end and stay there.