Precision · Dial-in chart
Precision GS30 grind settings
On the Precision GS30, start pour over at 3.9, espresso at 1.2 and French press at 7.3. Every other method, with the range to adjust in, is below.
The shape of this dial
The top line is the universal grind index every BrewMark recipe uses. The bottom line is the GS30’s own dial. The connectors show how one maps onto the other.
GS30 settings for each brew method
Start at the recommended setting, brew, then move within the range by taste. Sour or weak means go finer; bitter or harsh means go coarser.
| Method | Setting | Range |
|---|---|---|
| EspressoFine. Aim for a 25–30s shot and adjust from there. | 1.2≈ 330 µm | 0.4 – 2.2 |
| Moka potFiner than filter, coarser than espresso. No tamping. | 2.7≈ 460 µm | 2.2 – 3 |
| AeroPress (short steep)For 1–2 minute recipes. Go coarser for longer steeps. | 3.2≈ 500 µm | 3 – 3.6 |
| Pour over — V60 / coneThe reference point for most published pour-over recipes. | 3.9≈ 560 µm | 3.6 – 4.5 |
| SiphonMedium. Short contact over steady heat, so start here and taste. | 4.2≈ 580 µm | 3.8 – 5 |
| Pour over — flat bottomKalita, Orea and similar. Slightly coarser than a cone. | 4.5≈ 610 µm | 4 – 5.3 |
| Steep and release — Clever / SwitchSteep, then drain through a paper filter. If it drains slowly, go coarser. | 4.9≈ 640 µm | 4.2 – 5.6 |
| Drip / batch brewAutomatic brewers. Coarser to suit the longer contact time. | 5.1≈ 660 µm | 4.5 – 5.9 |
| CuppingMedium-coarse, for tasting side by side. Keep it the same across every bowl. | 5.3≈ 670 µm | 4.6 – 5.9 |
| ChemexThe thick filter needs a coarser grind to avoid stalling. | 5.9≈ 720 µm | 5.3 – 6.8 |
| French pressCoarse. Too fine here is the usual cause of a muddy cup. | 7.3≈ 840 µm | 6.7 – 7.9 |
| Cold brewCoarsest setting you have. 12–18 hours of contact. | 8.4≈ 930 µm | 7.9 – 9.2 |
≈ µm is the particle size, approximate, after Honest Coffee Guide’s scale for the GS30. It is not the maker’s microns per click, which measure how far the burrs move.
How much room you have to adjust
That is the resolution you actually have to work with on the GS30. Where the number is small, a single step moves the cup more than you would expect — so change one at a time and taste before moving again.
Coming from another grinder?
Convert a grind setting to the GS30
If a recipe quotes a setting for a different grinder, this maps it onto the GS30’s dial using the same curve the chart above is built from.
Converting between two grinders that are not this one? Open the full converter.
How these numbers were worked out
Every grinder gets mapped onto a shared 0–100 grind index, where 0 is espresso-fine and 100 is the coarsest useful setting. Five reference points on the GS30 are placed on that scale — espresso, moka, filter, French press and coarse — and the settings in between are interpolated.
The GS30 joined the catalog in October 2026. Its reference points were worked out rather than read off a maker’s chart: Honest Coffee Guide places every setting on this grinder on one scale of particle size, and each point sits where that scale reaches the size the same method lands on across the grinders we have checked. We couldn’t confirm whether these numbers are printed on the grinder or counted from where the burrs touch, so check your own dial before relying on the ends of the range. That makes them a starting point rather than a specification, and they are marked unverified until a manufacturer’s chart confirms them. Sources: Honest Coffee Guide.
The GS30’s dial is interpolated linearly between those reference points, which is the right model for its burr geometry.
The result is that “medium-fine” resolves to a real number on this grinder rather than a vague instruction. It is a starting point, not a guarantee — burr wear, bean density and roast level all move the target, which is why every row above gives a range as well as a number.
Free wall chart
Put the GS30 numbers next to the grinder
The main methods on one sheet, laid out on the GS30’s own dial so you can see where the settings bunch up. Print it, pin it, stop reaching for your phone with wet hands.
Or have the GS30 chart emailed
The same settings, sent once, for when you are standing at the grinder and nowhere near a printer.
One email with the chart. Nothing else unless you ask.
Make these numbers yours
This chart is the same for every GS30 in the world. Log what you actually brewed and it stops being — the app remembers the setting that worked for your beans and shifts the starting point toward it. Free on iOS.
Get the iOS appGrinders that dial in like this one
Similar burrs, scale or dial range — which means settings translate between them more predictably than across the whole catalog.
Own a GS30? Tell us your setting
If you’ve dialled in a method on your own GS30, the number you landed on is the best evidence there is. Readings are checked by hand before anything changes here.