Hario Ceramic Coffee Mill Mini Slim Plus: A Practical Guide

The Hario Mini Slim Plus is probably the most bought hand grinder in the world. It's cheap, it's compact, it uses ceramic burrs, and it grinds coffee that tastes noticeably better than anything you'd buy pre-ground. For someone starting out with manual brewing or needing a travel grinder, it's one of the first recommendations that comes up for good reason.

But it's not perfect, and understanding what it does well versus where it struggles will help you get the most out of it. I'll cover how it performs, how to use it properly, and who should actually buy one.

What the Mini Slim Plus Is

The Hario Mini Slim Plus is a manual hand grinder with a ceramic conical burr. It replaces the older Mini Slim model (which used a slightly different adjustment mechanism) and adds a slightly more secure grind size adjustment system.

At 24mm burr diameter, it's on the small side even for hand grinders. The body is a transparent plastic tube about 18cm tall and 4.7cm in diameter, making it thin enough to slip into a jacket pocket or water bottle pouch. It holds about 24g of whole beans, which is enough for a double pour-over or two standard AeroPress doses.

The grind size is adjusted by turning the inner burr carrier via a small nut at the bottom of the handle assembly. Tightening moves you finer, loosening goes coarser. There are no click stops, so you adjust by feel and counting turns from the zero point (where the burrs just touch).

Hario lists it as compatible with drip, pour-over, and filter methods. For espresso, it technically grinds fine enough for Moka pot. For a pump espresso machine, it's genuinely not suited.

Grind Quality: What to Expect

The honest answer is that the Mini Slim Plus grinds well enough for pour-over and drip but not as consistently as grinders at two to three times its price.

The 24mm ceramic burrs produce a somewhat wide particle distribution at every setting. There are more fines mixed in with the main particles than you'd get from a Comandante C40 or even a Hario Skerton Pro. This shows up as slightly faster filter draws and a muddier cup if you're brewing with technique-sensitive methods like a V60.

For basic pour-over with a Chemex or automatic drip machine, you won't notice the inconsistency much. The cup is vastly better than pre-ground. But if you're working on extraction precision, brewing third-wave single origins, or using a flat-bottom brewer like a Kalita Wave, the Mini Slim Plus eventually becomes the limiting factor in your cup quality.

For AeroPress, it's genuinely excellent. The AeroPress is forgiving of grind inconsistency because you're forcing water through under pressure regardless of particle size distribution. This is where the Mini Slim Plus shines.

French press is workable but produces more sediment than a Skerton or larger-burr hand grinder. Coarser settings still have significant fines.

How to Adjust and Use It

Setting Grind Size

Start from zero, which is where the burrs just touch with no beans. You'll feel a slight friction when the ceramic surfaces contact. From there, back the adjustment nut out (counterclockwise when viewed from below) to open the gap.

Common starting points: - AeroPress (finer/faster recipe): 4-6 half-turns from zero - AeroPress (coarser/immersion): 8-10 half-turns - Pour-over V60: 8-12 half-turns - Chemex: 12-16 half-turns - French press: 16-20 half-turns

These are rough guides. The actual output varies between individual units due to manufacturing tolerances in the ceramic burrs. Keep a note of what worked for your specific grinder.

Grinding Technique

The crank is small. Grip the glass or plastic body in one hand and turn the crank with the other. The catch jar unscrews from the bottom and can be used as your grounds cup directly, which makes it easy to pour directly into an AeroPress or brewer.

24g of coffee takes about 2-3 minutes at a medium grind setting. At espresso-fine settings, it's slower and harder to turn. At coarse French press settings, it's much easier.

If the grind feels gummy or the crank is hard to turn, you might have oily beans. Dark roasts with visible oil on the bean surface can clog ceramic burrs faster than lighter roasts.

Cleaning and Maintenance

The Mini Slim Plus disassembles easily. Unscrew the adjustment nut, slide out the inner burr, and brush everything with a stiff brush or a dedicated grinder cleaning brush. Do this every 2-4 weeks depending on use.

Don't wash the ceramic burrs under water unless you dry them immediately and completely. Wet ceramic burrs can develop surface residue over time. A dry brush is usually sufficient.

The plastic body and glass/transparent container can be washed with soap and water. Let everything dry before reassembling.

Ceramic burrs don't need replacement as often as steel. Hario's ceramic burrs typically last 500g-1kg of coffee before dulling noticeably. For light home use, that's many years.

How It Compares to Similar Grinders

Vs. Hario Skerton Pro

The Skerton Pro is Hario's larger hand grinder with a bigger burr and a stabilizing bar for the upper burr. It's around $50-60 vs. The Mini Slim Plus at around $30. The Skerton Pro produces more consistent coarse grinds, which matters for French press. For AeroPress and pour-over, the difference is smaller but the Skerton Pro still edges it out.

Vs. Timemore C2

The Timemore C2 costs around $70 and uses steel burrs with a much better bearing system. It produces significantly more consistent grinds across all settings and grinds faster with less effort. If your budget allows it, the C2 is a better grinder by every metric except price.

Vs. Comandante C40

Not a fair comparison. The C40 is $260 and outperforms the Mini Slim Plus so thoroughly that they're in different categories. If you're already in the conversation about Comandantes, the Mini Slim Plus isn't the grinder you're shopping for.

For context on how hand grinders at various price points stack up for drip and filter brewing, our best coffee grinder guide covers options from budget to premium alongside electric alternatives.

Who Should Buy the Hario Mini Slim Plus

It makes sense for a specific set of people:

You're just getting into specialty coffee and want to see if grinding fresh makes a noticeable difference before spending more. It does, and the Mini Slim Plus is a low-risk way to find out.

You travel frequently and want something genuinely compact. It fits in a toiletry bag. Ceramic burrs don't trigger airport security like metal tools occasionally do.

You're buying a gift for someone who drinks AeroPress or pour-over coffee and doesn't have a grinder yet.

You want a secondary grinder for work or a secondary home.

If you're already grinding fresh coffee and want an upgrade from entry-level, skip the Mini Slim Plus. Our top coffee grinder roundup has better options at the $50-150 range that will give you a meaningful quality jump.

FAQ

How many turns for pour-over on the Hario Mini Slim Plus?

A starting point is 10-14 half-turns from zero for a standard V60 with a medium roast. Adjust based on flow rate. If your water drains in under 2 minutes, go finer. Over 4 minutes, go coarser.

Can I use it for espresso?

For Moka pot, yes. For a pump espresso machine, no. The small burr diameter and looser tolerances in this price range can't produce the tight grind required for consistent espresso extraction.

How long does it take to grind?

Around 2-3 minutes for a 20g dose at a pour-over grind setting. AeroPress fine settings take a bit longer. Coarser settings are faster.

How do I know when the burrs need replacing?

If you're grinding at the same setting but your coffee is tasting notably weaker or faster-draining than before, the burrs may be worn. Replacement ceramic burr sets for the Mini Slim Plus are available from Hario and cost around $10-15.

The Practical Verdict

The Hario Ceramic Coffee Mill Mini Slim Plus is exactly what it looks like: an affordable, compact, capable-enough grinder that beats pre-ground coffee by a meaningful margin. It's not the best hand grinder available. It's the best hand grinder for the money if compactness and entry-level price are your main requirements.

Get it for travel, get it to start a fresh-grinding habit, or get it as a gift. Expect good coffee, not perfect coffee.