Grind setting conversion
Fellow Opus vs Mahlkönig X54
Conical against flat — the Opus's scale curves where the other runs straight. The Opus is numbered 1–11; the X54 is numbered 1–15.
| Opus | X54 | |
|---|---|---|
| Brand | Fellow | Mahlkönig |
| Scale | Numbered dial | Numbered dial |
| Dial range | 1 – 11 | 1 – 15 |
| Burrs | Conical | Flat |
| Espresso → filter | 3.3 numbers | 6 numbers |
| Filter → coarse | 5 numbers | 6 numbers |
The same number means different things
Both grinders use a numbered dial, which makes it tempting to copy a number straight across. Setting 6 sits at grind index 60.7 on the Opus but 27.5 on the X54 — 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.
| Opus | X54 |
|---|---|
| 1.3 | 2 |
| 2.3 | 3.1 |
| 3.1 | 4.3 |
| 3.7 | 5.6 |
| 4.1 | 6.9 |
| 4.6 | 8.2 |
| 5.2 | 9 |
| 5.8 | 9.8 |
| 6.5 | 10.7 |
| 7.2 | 11.5 |
| 7.9 | 12.3 |
| 8.7 | 13.2 |
| 9.5 | 14 |
| X54 | Opus |
|---|---|
| 2 | 1.3 |
| 3.1 | 2.3 |
| 4.3 | 3.1 |
| 5.6 | 3.7 |
| 6.9 | 4.1 |
| 8.2 | 4.6 |
| 9 | 5.2 |
| 9.8 | 5.8 |
| 10.7 | 6.5 |
| 11.5 | 7.2 |
| 12.3 | 7.9 |
| 13.2 | 8.7 |
| 14 | 9.5 |
Side by side, by brew method
Where each grinder lands for the same brew, worked out from its own dial curve.
| Method | Opus | X54 |
|---|---|---|
| Espresso | 1.9 | 2.7 |
| Moka pot | 3 | 4 |
| AeroPress (short steep) | 3.7 | 5.6 |
| Pour over — V60 / cone | 4.4 | 7.7 |
| Pour over — flat bottom | 4.8 | 8.5 |
| Drip / batch brew | 5.2 | 9 |
| Chemex | 5.8 | 9.8 |
| French press | 6.9 | 11.2 |
| Cold brew | 8.4 | 12.8 |
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.
Fellow Opus
Mahlkönig X54
Dialing in the Opus
Marketed as all-purpose, and it genuinely does cover more range than the Ode, but the espresso end is workable rather than good — expect to chase it. Where it earns its place is the coarse end: cold brew and French press come out notably even. If you bought the Opus mainly for espresso, dial it as a brew grinder first and judge it there.
Dialing in the X54
Mahlkönig's home grinder, and much more conventional than the EK that shares its badge. Genuinely all-purpose with a usable espresso end, though the resolution down there is nothing like a dedicated espresso grinder's.
Own a different grinder?
Convert between any two of 78 models
The converter runs the same maths for any pair in the catalog.
Open the grind converter →Send me both charts
Every setting for the Fellow Opus and the Mahlkönig X54, side by side in your inbox.
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Switching grinders mid-bag?
Log a brew, say how it tasted, and BrewMark tells you which way to move — in whichever grinder’s numbers you are actually using. Free on iOS.
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