Hario Mini Mill Review: How Does The Slim Compare?

hario mini mill review

Please note: If you decide to purchase a product through a link on the site, we may earn a commission without additional cost to you. Learn More >

When you’ve seen a hand grinder, you’ve seen them all, right? I’ll admit I have a bit of an addiction when it comes to pocket-sized coffee grinders, and I can confidently say that I have pretty much tried them all. Well, maybe not all, but it’s a hell of a lot.

What I have discovered over the years is that almost all mini grinders come with inherent flaws. Hard to crank, difficult to dial in your grind setting, cheap parts, and bad fitting components are just a few issues I often run into.

However, the newest addition to my collection might be the grinder to rule them all.

I recently got my hands on the Hario Mini Mill coffee grinder. Over the past few weeks, I have been putting the Mini Slim through its paces. Since using the Slim, it’s ticked all of the boxes and has made light work of any whole bean coffee I’ve thrown into it!

Also, so far, the minor flaws I’ve discovered with this grinder are not deal-breakers.

Want to know more? Here’s my Hario Mini Mill review.


Hario Mini Mill Grinder: At a Glance

Just as you would expect from a mini coffee grinder, the Hario Slim is small. But even with its relatively compact size, it still fits nicely in my hand, and thanks to its curved body, I can form a decent grip. That’s a big thumbs up in my book!

Standing at around 7 inches in height, it takes up very little room on your kitchen counter, and if you’re on a camping trip, you could fit the Hario inside of your pocket or your rucksack bottle holder.

You get my point. It’s compact.

Let’s take a closer look.

Hario Mini Mill

Design And Aesthetics

Unlike the other coffee grinders offered by Hario that are typically made of glass, the Mini Mill’s construction is mainly plastic.

Is that a deal-breaker? No, not for me.

After all, this coffee grinder is best suited for throwing in your backpack without a second thought. It’s perfect for when you’re going on a camping trip or anytime you’re out in the sticks brewing coffee away from civilization.

Plastic is a safe bet – it’s not going to shatter into a thousand pieces, and it’s a hell of a lot lighter than glass.

However, don’t let the plastic outer shell fool you. Hidden inside of the plastic body, you’ll find a sophisticated ceramic burr grinding mechanism that can churn out various grind sizes with ease.

You want a fine grind for espresso, not a problem.

Need a grind for your AeroPress, easy-peasy.

French Press? The Mini Coffee Mill has that covered too.

hario slim mini mill size

The Hario Mill Mini uses ceramic burrs. Ceramic burrs are considered better than stainless steel burrs that seem to come in many new mini coffee grinders nowadays.

The ceramic material naturally reduces the heat caused by friction as you grind.

Less heat during the grinding process means that more of the flavourful oils locked inside of your whole bean coffee will make it to your cup rather than evaporate into the air as you grind.
More oils, more flavor!

Like the Hario Skerton Pro, which I reviewed here, the Mini Mill has done away with the old fiddlely lock nut to keep the crank handle in place in favor of a simple but well-fitting hex locking handle.

It takes no effort to lock the handle in place, and surprisingly it stays in place no matter how vigorously you crank the handle.

hex handle locking nut on the hario slim grinder

The clear plastic disk lid reassuringly snaps onto the bean hopper, ensuring that your whole coffee beans don’t fly all over the place when you decide to kick up your hand cranking a gear or two.

A nice feature on the Mini Mill that the other grinders in the Hario range have neglected is the cup size markings on the clear plastic collection chamber side.

However, I found that these markings weren’t truly accurate, more of a guesstimate – but with that said, I can see how they would be helpful if you were camping and didn’t have a coffee scale handy.

How Easy is The Hario Mini Mill to Use?

I’m sure you’ve grasped that the Mini Mill is a simple coffee grinder when it comes to design, but how easy is it to use?

Super-easy – no, really it is.

Remove the plastic disk lid and add your whole fresh coffee beans, place the lid back in place, attach the handle to the steel hex on top of the grinder, and you’re good to go.

top view coffee beans in hopper

fitting disk shaped lid to bean hopper

It’s worth noting that the bean hopper can hold roughly 24g of coffee, which should be more than adequate for one person.

As you crank the handle, your whole coffee beans slowly get pulled through the ceramic burrs and fall through into the clear plastic collection chamber – you can see, on the fly, how your coffee grounds are looking and adjust your settings if necessary.

Adjusting the Ceramic Grinding Burrs

Oh, adjusting the grind settings is easy too.

Just like the new Skerton Pro, the Hario Mini Mill uses a nut bolt below the grinding burs that clicks each time you lock in a grind setting.

You twist, it clicks, and the burrs move.

slim hario coffee mill grind setting adjustment

This system takes out a lot of the guesswork, and once you have dialed in your preferred grind, it’s as easy as clicking the dial a certain amount of times next time around.

To set, tighten the nut all the way up – you should see the burrs draw-in as you do this. I call this starting at zero.

Every click from here will adjust your grind more coarsely.

For example. I typically lock in anywhere from 8 to 10 clicks for my Hario V60 pour-over and often go for 15 clicks if I’m brewing in my French Press.

For you, it might be slightly different depending on how you like to brew your coffee – but this is a good starting point if you’re new to the Hario Mini Mill.

Ok, I don’t want to put a downer on all of the positives I’ve talked about so far. But the grind consistency with the Mini Coffee Mill isn’t going to compete with high-end commercial coffee grinders.

There I said it.

At this price point, you can’t expect it to.

The main problem with grind consistency is due to the movement of the burrs, it’s not so problematic in the fine settings, but as you edge up to a more coarse grind, it definitely becomes more noticeable.

The good news is that I have a solution. This little Hario Mini Mill Mod I came up with improves the consistency significantly. Kind of crazy that Hario hasn’t come up with a solution to this problem themselves?

How Fast Does it Grind?

I bet you’re wondering just how fast do the Hario Mini Mill grind. After all, you’re the one cranking on the handle – so just how much elbow grease is it going to take to get a decent cup of coffee?

I found that it takes me just over one minute to grind 20 grams of coffee on a medium setting (10 clicks +/-).

Hario Mini Mill click settings example

Not too shabby – definitely quick enough for something of this size, and actually, it outshines some of the more expensive hand grinders I have used in the past when it comes to speed.

The downside is that you can only grind enough for one person, so if you’re brewing coffee for more than one, you will find that you’ll have to keep refilling and cranking on the handle some more.

Hario Mini Mill Grind Consistency

The grind quality of the Hario Mini Mill is on par with the Skerton Pro and slightly better than other manual hand grinders in this price range.

The Mini Mill excels in the fine grind settings but becomes more inconsistent the coarser grind size you go, and finding uneven boulders in your French Press ground coffee isn’t uncommon.

Take a look for yourselves.

Below I have ground up some coffee using the Hario Mini Mill Slim at various fine, medium, and coarse settings.

fine grind
Fine Grind
medium grind
Medium Grind
coarse grind
Coarse Grind

The Verdict – Should You Get The Hario Mini Mill Slim?

The Hario Mini Mill has become my trusty sidekick this past few weeks, I’ve taken it everywhere, and it hasn’t let me down.

All in all, I think that it’s a really fantastic little coffee grinder for the price. But, remember, as, with all hand grinders, muscle and patience are a standard requirement.

If you’re looking for a pocket-sized burr grinder that can produce a high-quality, consistent grind at an attractive price point, this solid piece of Japanese-designed equipment will serve you well.

Seriously, You can’t go wrong, give this manual coffee grinder a go and step up your home brewing game!

But, if you want something that can churn out a bit more ground coffee and is better suited for home use, take a look at the Mini Mills bigger brother, the Hario Skerton Pro. I reviewed that here.

hario coffee grinder mini slim mill

What We Love

  • Ceramic conical burrs.
  • Super lightweight and portable.
  • Simple click wheel grind adjustment.
  • Take it anywhere.

Take Note

  • Only holds roughly 24g of coffee in the top chamber.
  • No anti-slip base doesn’t provide much traction while grinding.
  • List item


🔥 Check out the latest discounts over at Volcanica Coffee. One of our favorite online specialty coffee roasters > Click Here
Why Should You Trust Us
Mark has over 20 years of experience in the catering and hospitality sector. He takes his years of knowledge and expertise and applies it to critiquing coffee equipment and brewing gear.

Since the creation of the Bean Ground coffee blog in 2014, Mark and a small circle of coffee hobbyists have rigorously tested, reviewed, and researched coffee gear. In most cases, they have purchased the items themselves with the sole intention of rating and evaluating.

In that time, they have built up a list of quality points to look for and what makes specific equipment better than others. They cut through the noise and marketing hype that often surrounds products to give you their unbiased opinions so you can make clear decisions on your next purchase.

About The Author

Scroll to Top