KitchenIQ 50009 vs. Zwilling 4-Stage Manual Sharpener Side-by-Side Comparison

Anh Ngo
Anh Ngo
Reviewer
Nguyen Ntk
Nguyen Ntk
Visual Specialist
Reviewed
Our recommendations are made independently through research and testing following our review procedure. We may receive commissions from purchases made via our links at no additional costs to you.
Tested Using Methodology v1.1
Updated Nov 28, 2022
Tested Using Methodology v1.1
Updated Nov 28, 2022
KitchenIQ 50009 Edge Grip 2-Stage Knife Sharpener Testing and Review
Zwilling Manual Knife Sharpener Review
Knife Sharpener type
manual
manual
Power
0W
0W

Our Verdict

6.2
Overall Score
  • Performance (50%)
    4.3/10
  • Design (15%)
    8.1/10
  • Ease of Use (35%)
    8.2/10
6.2
Overall Score
  • Performance (50%)
    4.7/10
  • Design (15%)
    7.5/10
  • Ease of Use (35%)
    7.8/10

The KitchenIQ 50009 2-stage and the Zwilling 4-stage manual sharpeners have a lot more in common than their looks and prices may suggest.

Though distinctive in size, the two sharpeners share a strong, solid, sturdy build. Each has unique selling points: The former sports a compact size and an edge-gripping base, while the latter sharpens and hones at two different grind angles. 

Unfortunately, neither performed particularly well in our tests. In fact, they were among the slowest and least effective sharpeners. The Zwilling did slightly better in most categories but that didn’t offer much of a consolation, especially considering its high price. 

There are plenty of other manual pull-through sharpeners that can do a better job. Check out our rating tables to find the right one for you.

Performance

4.3
Performance Scores
  • Sharpening Time to Cut a Lemon (35%)
    1.0/10
  • Maximum Sharpness Achieved (20%)
    6.0/10
  • Edge Smoothness (20%)
    6.5/10
  • Material Retention (25%)
    6.0/10
4.7
Performance Scores
  • Sharpening Time to Cut a Lemon (35%)
    1.0/10
  • Maximum Sharpness Achieved (20%)
    7.0/10
  • Edge Smoothness (20%)
    7.3/10
  • Material Retention (25%)
    6.0/10
1.0

Sharpening Time to Cut a Lemon

1.0
  • Sharpening Time: 3 minutes 35 seconds
  • Cutting Feel: Swift and smooth

The KitchenIQ took 215 seconds, or more than 3 minutes to sharpen a knife to the point where it could cut through a big lemon in one single swipe. This may not sound like a terribly long time, but we generally expect faster results from handheld sharpeners. In fact, similar one-stage or two-stage devices take less than half that time to get to the same level. For example, it was 105 seconds for the Sharpal, and 65 seconds for the SunrisePro.

  • Sharpening Time: 3 minutes
  • Cutting Feel: Slightly forced

The Zwilling is, sadly, one of the slower sharpeners even among its category. It took 180 seconds to sharpen a sandpaper-destroyed knife to the lemon-cutting level, and even then, the cutting motion didn’t feel completely effortless. Three minutes may feel like nothing if you’re used to working with a whetstone, but for a convenient device like this one, one would expect a much shorter time.

6.0

Maximum Sharpness Achieved

7.0
  • Sharpening Time: 6 minutes
  • Sharpness Level: 7 (ripe tomatoes, 1 swipe)

An additional 3 minutes on the KitchenIQ took the test knife from the lemon to the ripe tomato level, and that was its peak sharpness with this device.

Though this is below what most sharpeners can achieve, at this level, the knife’s still capable of most cutting tasks, save for perhaps precision cutting and thin slicing. 

We conducted this test several times over the span of six months and used the device in our kitchen throughout that time. The results were consistent, so at least we can conclude that its abrasives will take a long time to wear down.

  • Sharpening Time: 6 minutes
  • Sharpness Level: 8 - (Chicken breast with skin, 2 swipes)

While it failed quite miserably in the speed test, the Zwilling sharpener got decent results when given more time. The test knife passed the tomato test with flying colors and could cut through the muscle and runny skin on a fresh piece of chicken breast with two light and easy swipes. 

We tried it on beef tendon too, which it took two heavy strokes to sever. The device was marked as failed for this level, but we think its efforts would be sufficient for most food prep needs.

6.0

Material Retention

6.0
Kitchen IQ Material Retention
Kitchen IQ 50009 Material Retention
  • Sharpening Time: 1 minute
  • Target Sharpness:

Since its tungsten carbide blades do most of the sharpening, the KitchenIQ peels off more steel from the blade than do most other multi-stage sharpeners. It produces more dust than coarse swarf, suggesting that it acts more like a grinder rather than a serious peeler. This suspicion is confirmed by the relatively fine edges it creates. This was true even when we deliberately applied more force while pulling the knife through. 

Unfortunately, the extra pressure didn’t help much with improving the knife’s sharpness.

ZWILLING Material Retention
ZWILLING Material Retention 1
  • Sharpening Time: 1 minute
  • Target Sharpness:

For the sharpness level it could achieve, the Zwilling shaves off way too much steel from the knife. We couldn’t help but shudder at the long curls of swarf coming out of the Coarse slot.

Most other devices employ ceramic rods for honing the knife, so even though this function comes in the form of blades on this sharpener, we really didn’t expect the ceramic to be so harsh on the knife edge.

6.5

Edge Smoothness

7.3
Kitchen IQ Edge Smoothness

The KitchenIQ produces an ok edge with no major chips or burrs. The primary edge looks narrow, with visible horizontal grooves and tiny metal grains and fragments. The ceramic rods seem to do their job of refining the edge, making for better results compared to the Smith’s or SunrisePro.

ZWILLING Edge Smoothness

Although the Zwilling peels a lot off the knife, we have to give it credit for the pretty edge it left. There are long and deep grooves along the edge—we could tell from the swarf alone—but overall, the edge is straight and consistent, and without visible chips or teeth. 

However, with its ceramic blades chipped after only a few uses, we’re at best skeptical about the device’s ability to maintain delivery of this edge quality.

Design

8.1
design Scores
  • Build Quality (75%)
    8.7/10
  • Grip (25%)
    6.5/10
7.5
design Scores
  • Build Quality (75%)
    7.8/10
  • Grip (25%)
    6.5/10

In the Box

KitchenIQ 50009 In the Box
  • The KitchenIQ 50009 edge grip knife sharpener

The device comes in a simple clamshell package. It has four color options. Interestingly, each color is sold at a different price, though they’re all affordable.

ZWILLING In the Box
  • The Zwilling 4-stage sharpener
  • Instruction leaflet

The Zwilling 4-stage sharpener comes protected by a plastic blister pack, with a simple instruction manual. The device is solid and heavier than most others.

Dimensions

Kitchen IQ 50009 Dimensions
  • Length:
    3.7" (9.4 cm)
  • Width:
    2.0" (5.1 cm)
  • Height:
    1.8" (4.6 cm)
  • Weight:
    2.0 oz (57 g)

ZWILLING Dimensions
  • Length:
    9.3" (23.6 cm)
  • Width:
    1.7" (4.3 cm)
  • Height:
    3.1" (7.9 cm)
  • Weight:
    11.2 oz (318 g)

8.7

Build Quality

7.8
KitchenIQ 50009 Build Quality

The KitchenIQ deserves a shoutout for its excellent build quality despite its cheap price. The whole sharpener is solid and sturdy. Its parts all fit together seamlessly, leaving no unexpected gaps. We actually dropped it from our countertop a couple times, and it took it well. Even afterward, we didn’t observe any rattling or loose components.

The silicone grip cover was nice to the touch and comfortable to hold throughout the sharpening session.

ZWILLING Build Quality

While its design leaves a lot of room for improvement, the Zwilling is overall a robust, well-built sharpener. Its body feels rigid and solid, the frame and paddings are made of high-quality materials, and every part fits together nicely, leaving no gaps. 

Unfortunately, the device’s weakness is its most critical part: the ceramic sharpening blades. 

Normally, ceramic is used to make honing rods on pull-through sharpeners, but on the Zwilling, it’s employed in the shape of rectangular sharpening blades with their own delicate edges. The chipping we found on those blades after only a few days of testing proved that this break from the norm was an error of judgment. Obviously, being hard but brittle, the ceramic blades couldn’t withstand a rough steel knife edge.

6.5

Grip

6.5
KitchenIQ 50009 Grip
  • Material:
    Silicone

We really like the feel of the grip — it’s soft but offers good friction. It has an ergonomic shape and is connected directly to the base, thus offering great stability.  Its tiny size, however, feels awkward in even smaller hands. Users with large hands will have problems finding a safe place for their fingers.

ZWILLING Grip
ZWILLING Grip 1
  • Material:
    ABS, EVA

The Zwilling’s grip looks and feels fancier than most other devices’, but we wish the design were more simple. The thumb holder was awkward to grasp, and both of us testers couldn’t seem to align our fingers with the finger nubs. 

We also thought the space between the grip and the base to be excessive — a lower height and center of gravity would immensely improve the device’s stability.

Working Section

KitchenIQ 50009 Working Section
  • Levels of Sharpening:
    Coarse, Fine
  • Abrasive:
    Tungsten carbide blades, ceramic rods
  • Mechanism:
    Pull through
  • Sharpening Angle:
    20 degrees

The KitchenIQ offers two levels of sharpening. While the slots themselves are more or less the same size as those on other devices, the whole working section is rather small and doesn’t work well with larger and thicker knives.

ZWILLING Working Section
  • Levels of Sharpening:
    Sharpen, Polish
  • Abrasive:
    Ceramic blades
  • Mechanism:
    Pull through
  • Sharpening Angle:
    15 degrees, 10 degrees

The Zwilling sharpener has a long working section, covering two types of edge angle: standard and Asian. We find the alleged grind angles of 15 and 10 degrees to be surprisingly small—standard knives typically come at 18-22 degrees and Asian knives, 13 - 15 degrees. An edge angle of 10 degrees is probably more appropriate for razors than kitchen knives.

Angles aside, we like how the working section is closer to the base than the rest of the device is. This helps lower the center of gravity even only by a little, and improves the overall balance.

Base

KitchenIQ 50009 Base
  • Material:
    Silicone
  • Feet Type:
    Edge gripper

Not only is the layout of its working section different from most other devices, the KitchenIQ’s base is special too. It’s a thick silicone pad that covers the grip and extends all the way to the base, creating lots of friction with any flat surface. The cutout in the middle of the base forms an edge grip, allowing you to attach it to the countertop or table edge (as long as that edge is 90 degrees).

ZWILLING Base
ZWILLING Base 1
  • Material:
    Plastic
  • Feet Type:
    EVA pad

The Zwilling sharpener has a solid, flat base, with a high-quality anti-slip pad underneath. But this is yet another area where it suffers from bad design.

The base is long and narrow, which is not ideal for its considerable height. The pad only partially covers the base, leaving its border hanging in the air— the pad basically adds height while further reducing the already modest width. As a result, the device is very prone to rocking.

Ease of Use

8.2
usability Scores
  • Slot Arrangement (10%)
    7.0/10
  • Insertion (20%)
    7.0/10
  • Pulling Through (10%)
    7.0/10
  • Stability on a Clean Surface (40%)
    10/10
  • Stability on a Wet and Dirty Surface (20%)
    7.0/10
7.8
usability Scores
  • Slot Arrangement (10%)
    10/10
  • Insertion (20%)
    9.0/10
  • Pulling Through (10%)
    7.5/10
  • Stability on a Clean Surface (40%)
    7.5/10
  • Stability on a Wet and Dirty Surface (20%)
    6.0/10
7.0

Slot Arrangement

10
Kitchen IQ Slot Arrangement

The KitchenIQ employs a different slot layout than most others of its type: The coarse slot is placed further from the grip than the fine one. If you’ve used other pull-through sharpeners before, this layout will take some time to get used to. Otherwise, it’s not a problem: The slot names (Coarse and Fine) are printed on both sides of the working section, so pay a little attention and you’ll do it right. This also makes the device south-paw friendly.

ZWILLING Slot Arrangement

The Zwilling has more sharpening slots than most others, but its layout is straightforward. Half of the working section is for standard blades and the other half Asian, as indicated by the print underneath. The slots progress in the same order for each angle type, with their coarseness level printed on their sides.

A transparent plastic cover can be slid over the area you’re not working on, so it’s rare that you will misplace your knife while sharpening.

7.0

Insertion

9.0
Kitchen IQ Insertion

You may notice that the tungsten blades in the Coarse slot have distinct corners that protrude from the plastic frame. If you use too much force or are too fast with insertion, your delicate knife edge may end up raking across one of those surfaces and risk chipping or deforming.

Also, the tiny size of the KitchenIQ means the slots are jammed together and are very close to the grip. There’s a real danger of cutting yourself if you’re not mindful while sharpening your knives.

All that being said, insertion was not challenging. We measured the actual openings and found to our surprise that they’re some of the widest among all the devices we tested (6mm).

ZWILLING Insertion

It doesn’t have the widest slot openings, but insertion is still effortless with the Zwilling. Its lowered working section and the rather spacious grip do offer a sense of confidence and safety in this regard.

7.0

Pulling Through

7.5

The KitchenIQ’s sturdy working section and strong base allows for steady operation. Pulling through was effortless, though it’s easy to cut into the plastic frame underneath the sharpening panels if you go too fast.

We noticed that the ‘brace’ is rather loose on this device — the sharpening rods don’t seem to grip to the blade very tightly. This contributes to the rather mediocre sharpening performance.

ZWILLING Pulling Through

The problem with abrasive blades is that sometimes they lose grip of the knife edge, letting it glide through untouched. The fact that its blades are made of ceramic instead of tungsten carbide as a typical sharpener’s would be doesn’t exempt the Zwilling from this issue. 

The thick frame around the slots, while offering great support, does obstruct the knife tip at the end as the downward force is still in place. It gets nicked from time to time, though this doesn’t affect the knife edge or sharpness.

10

Stability on a Clean Surface

7.5
Kitchen IQ 50009 Stability on a Clean Surface

With a grip and base made from one solid piece of tough silicone, the KitchenIQ stood perfectly still on a clean countertop as we pulled a knife through it. It has a low center of gravity, so regardless of the force used, the device didn’t wobble one bit.

We tried it on the countertop edge, too, which it’s designed to work on, and were happy with how well it gripped the edge.

ZWILLING Stability on a Clean Surface

The Zwilling’s heavy weight (a whopping 11 ounces) and solidness couldn’t cancel out the effect of its massive height to stabilize the device. Nor did its narrow base and an even narrower anti-slip pad allow it to fare well in our test. The sharpener kept losing its balance.

7.0

Stability on a Wet and Dirty Surface

6.0
Kitchen IQ 50009 Stability on a Wet and Dirty Surface

Like most other devices, the KitchenIQ’s silicone base couldn’t keep it in place on a dirty countertop. To its credit, the device slid but did not shake or wobble like the taller units we tested. Still, given how its grip is so close to the sharpening slots, you run the risk of cutting yourself if things slip. 

The same was observed on a wet and slippery edge: no wobbling, but the silicone foot doesn’t help much in keeping it from gliding along the edge.

ZWILLING Stability on a Wet and Dirty Surface

The oil- and salt-tainted countertop only amplified all the design problems on the Zwilling. We could only keep it in place with excessive force on the grip, and so we highly recommend ensuring your countertop is dry and clean before using this sharpener.