1Zpresso K Ultra Review:
The Manual Grinder That Does It All

1Zpresso is our favorite manual grinder manufacturer. Every grinder we’ve tested from them has been superb and they’re continuously adding to their range so no matter what your specific grinding needs are, they have an option for you. We were late to the game with testing one of their top offerings, but it was worth the wait to get to do this 1Zpresso K Ultra review.

It came as no surprise that the 1Zpresso K Ultra is another excellent manual coffee grinder that does exactly what it claims to. With the ability to grind for all brewing methods, it’s a great “jack of all trades option” though its main purpose is pour over/drip. If espresso is your main brewing method, then we recommend the 1Zpresso J Ultra instead.

Having used a lot of manual grinders in our careers, we know you need to spend time with one to really understand it. So we’ve taken that time with the K Ultra and are now sharing our in-depth, unfiltered thoughts. Let’s get to it:

In Brief: 1Zpresso K-Ultra Review

1. 48mm Heptagonal Burrs

The K-series of 1Zpresso grinders feature heptagonal burrs and they’ve had a makeover in the K Ultra model. Now, the high-quality 48mm stainless steel burrs offer even greater precision, accuracy, and speed. (On average, it took us 45 seconds to grind 30g for espresso and around 25 seconds for pour over.)

Interestingly, there’s no base which makes cleaning the burrs an absolute breeze.

2. 20 Micron Adjustments

Each click of the grind adjustment dial moves the burr 20 microns. This allows you to fine-tune your grind size for a range of brewing methods from espresso to drip.

Whilst the J Ultra allows even greater precision (8 microns), the K Ultra is still a great all-rounder that will suit a huge number of people.

3. Full Range of Brewing Methods

With a range of 100 clicks, this manual grinder will allow you to make whatever coffee takes your fancy – from Turkish coffee all the way to French press or cold brew.

4. Foldable Handle

To make the K Ultra more compact for travel, the handle folds down next to the body of the grinder. This is a slick, nice feature found on the latest 1Zpresso grinders though only time will tell if constantly rotating the handle in/out of place causes it to fail with continued use.

5. 35g Capacity

You can grind enough coffee for 2 people thanks to the 35g capacity. Just remember that the more coffee you need to grind, the longer it will take.

6. Exterior Adjustment Dial

Easily switch between settings with the numbered dial on the top of the K Ultra. The numbers run from 0 to 9 with 10 clicks between each number.

7. Magnetic Catch Cup

The grounds catch cup securely attaches to the bottom of the grinder with strong magnets. I find this easier to remove than a screw-on catch cup (like the K Pro) but you do need to ensure it’s securely fastened to avoid dropping it on your toes!

First up is the numbered adjustment dial at the top of the grinder. This, combined with the helpful settings chart (in the manual and below), makes finding the correct range for brewing your preferred method of coffee really simple.

It also means that changing between brewing methods is very easy.

With just a quick twist of the top of the grinder, you can move from espresso to pour over or from AeroPress to French press.

Next, there’s the high-quality 48mm stainless steel burrs. In addition to being precise and smooth, they also make grinding fast too.

I will caveat this with the fact it’s a manual grinder, Katie has very small hands and struggles to grind it at finer settings as her hand isn’t big enough to firmly grip the grinder. She’s 5’2″ for reference. If you struggle with grip strength then manual grinders will all be very difficult for you to use.

It took us around 45 seconds to grind 30g at espresso fineness, and around 25 seconds for pour over.

We find the magnetic catch cup much easier than the screw-on one found on the K Pro. Though this is partly because I tend to screw it on too tight, leaving my wife unable to take it back off.

The magnets are impressively strong so it’s unlikely to fall off. But, when removing your freshly ground coffee, we found it best to hold the catch up still and twist the top of the grinder off. If you do it the other way, you’ll likely throw ground coffee everywhere – learn from my mistakes!

Choosing the Right Grind Size

Getting the grind exactly right for whatever beans and brewing method you’re using will take a little practice. But 1Zpresso offers a handy guide to ensure you’re in the right area to start:

Brewing Method	Range Start	Range End
Turkish Coffee	2.0	3.5
Espresso	3.0	4.5
AeroPress / Moka / Drip Coffee Maker	5.0	7.0
Siphon / Pour Over	8.0	9.0
French Press / Cold Brew	9.0	10

We got a good espresso at setting 3.2 using medium roast beans.

We’ve been brewing some medium-light roast Thai coffees at setting 6.4 in our AeroPress recently.

When we used our light roast Yirgacheffe beans for pour over, we got the best results at setting 7.8.

As there is only a 100-click range, it shouldn’t take much experimentation to find the right setting for you.

The downside is that if you’re into espresso and want to precisely dial in your shot, the K Ultra’s 20-micron gaps are too big. So, if espresso is your jam but you still want the option of grinding for different styles of coffee maker then the J Ultra is the better 1Zpresso grinder for you.

The Looks

As manual grinders go, I think the 1Zpresso K Ultra looks great.

It’s simple, sleek, and modern with a choice of two colors – either iron gray (our favorite and the one we used/photographed in testing) or silver. That said, if minimalist modern designs are your thing, you might prefer the looks of the X Ultra.

Compared with the other grinders in the K series, the K Ultra has a more rounded look. However, it still has familiar elements like the silicone sleeve for grip (in dark gray or brown) and the foldable handle with a wooden knob. When something looks great, why change it?

For me, the rounded edges are more aesthetically pleasing than the harsh corners of the previous generation, the K Max. The slightly slimmer body also adds a nice curve to the grinder which is easier on the hand and the eyes.

The Build

We’re long-time fans of 1Zpresso grinders. So we don’t really question the build quality: we know they’ll be superb. Every grinder in their range is solidly built with well-machined parts that fit together nicely. I dropped it about a week after getting it and it survived just fine.

Where the K Ultra (and all 1Zpresso grinders) really excel is in the quality of the burrs.

However, a few people (including product engineers) have raised concerns to us about the fold-away handle. As it twists into place, they worry that it will create a weak point that may break over time.

Obviously, the K Ultra is too new and we’ve not had it nearly long enough to know whether or not this is true. I suspect it will be years of continuous use before the handle fails (if it ever does.) But we feel it’s worth mentioning.

The K Ultra does come with a 1-year warranty (and great customer service) if you do have issues. But if the handle fails 5 years from now, it won’t be covered.

That said, we’d expect you to get a decade of normal use out of the K Ultra and its stainless steel burrs. 1Zpresso claims you’ll be able to grind 100-200kg of coffee. Which, wild variance aside, is somewhere between 7 to 13 years of daily grinding.

It’s much more likely you get distracted by a newer, shinier grinder than you use it to the point that the burrs no longer grind consistently.

At 7.3 inches tall and with a diameter of 2.4 inches, it’s easily small enough to chuck in your bag. Plus it comes with a nice carry case that holds the included cleaning tools too.

As consistent sized particles lead to even extraction and better-tasting coffee, the grind consistency is ultimately the most important aspect of any grinder. So we spent a lot of time testing for all brewing methods when writing this 1Zpresso K Ultra review.

And the K Ultra doesn’t disappoint with excellent grind consistency across its impressive grind range.

That said, things started to get a little uneven at the very coarsest settings. (This is true with most grinders.) But it didn’t negatively affect our French press flavor.

At the finest sizes, it’s very consistent. Which is where it matters most.

We also had no issues with static or fines getting stuck in the grinder. We’ve never really found this to be an issue on any 1Zpresso grinder we’ve used as long as you clean it regularly. If you don’t clean it weekly then the fines start to build up.

I’m a big fan of how easy it is as it makes it much more likely it’ll actually get cleaned. Ones that are too complicated or have too many small parts that can get lost tend to get forgotten. And an unclean grinder will negatively impact what your coffee tastes like and the longevity of your grinder.

Just remember to never clean your grinder with water.

Instead, use the soft brush and little rubber air blower that are included with the K Ultra to clean all the small particles out of the burrs and interior of the grinder.

Calibrating your K Ultra Grinder

As you need to disassemble the grinder to clean, you’ll need to calibrate it after cleaning every time.

Luckily it’s very easy to calibrate your K Ultra grinder. Just follow these steps:

Simply turn the dial to 0 without the burrs screwed into place. Then push up on the burrs from underneath so they are “closed” and screw the nut at the top of the grinder until it is tight.

If you need to adjust the calibration, you can turn the thumb nut at the top inside the grinder which will move the dial clockwise or anticlockwise until it lines up at 0.

We never had any issues with getting it to line up but if you’re still unsure, 1Zpresso explains it in much more detail – you can read it here.

To look at, you might not instantly realize you’re looking at 2 different grinders.

The J Ultra (which is an upgraded version of the superb J Max) has a very similar look and feel to the K Ultra with its curved edges, slimmed-down body, magnetic catch cup, and foldable handle. Visually, the most obvious difference is the different colored handles.

It’s only when you go a little deeper that you find the big differences:

For starters, the J Ultra has 48mm titanium-coated burrs. These will last longer than the 48mm stainless steel burrs on the K Ultra. That said, with normal use, we’d expect the K Ultra burrs to last up to 10 years, so maybe this isn’t something to worry about too much.

Next, the J Ultra has 8 microns per click compared to the K Ultra’s 20 microns giving you way more precision and control. You’ll really notice this difference if you’re making espresso as you can dial in your shots with way more control over the exact grind size with the J Ultra.

Both grinders cover all grind sizes but due to the smaller gaps between clicks on the J Ultra, it’s slightly cumbersome if you’re frequently switching between brewing methods.

Finally, the J Ultra is considerably cheaper than the K Ultra. Around $80 or so cheaper (based on 1Zpresso’s RRP.)

For us, having more precision with the same range for less money makes this a no-brainer. The J Ultra is our favorite manual grinder and we’d pick it every time.

However, if you’re planning to constantly jump between pour over and French press then you may find the convenience of the K Ultra worth the extra cost.

Read next: Our Complete 1Zpresso J Ultra Review

Pick Your Winner

It’s fast, it’s accurate, it’s easy to use, and it covers all the coffee brewing methods.

But (and it’s a big but), the downside is that the J Ultra is a better grinder for less money. As long as you’re happy to mess around with 200 clicks or more between settings, that is.

To be honest, we’d 100% take the J Ultra over the K Ultra every time. However, if the price was closer and we didn’t brew espresso, then the K Ultra would definitely be a strong contender.

Do you agree?

Don’t forget to Buy Your 1Zpresso K Ultra Today

Matt Woodburn-Simmonds

Matt's coffee obsession started in 2006 when working as a Barista. A tendency to turn up to work hungover kickstarted his coffee journey which quickly turned into a love affair. As he moved on to work as a Restaurant Manager and Sommelier, the obsession continued to grow. Now, his passion is helping others to enjoy better coffee at home.