To Find the Best Knife Sharpeners (Including Whetstones), I Sharpened Dozens of Blades

People tend to ask you about knives when you've spent years working as a chef. Expressly, which new knife sets should they buy because their old one is dull. I want to tell them to buckle down and sharpen their old knives. But, I admit, there’s a sticking point: knowing how to do it. 

While they could ship them off or take them to a local business to sharpen them, a sharpening stone (a.k.a a whetstone) is my pick. It took a lot of practice to get the method right. (I was an Eagle Scout and dulled many knives in my first attempts to sharpen a blade.) But eventually, I got it, and once you do, you rarely get it wrong again. As a chef, I taught my staff how to sharpen the $300 knives they had no idea how to maintain because no one had taken the time to help them. During the pandemic shutdown, I had extra time and even did a live stream demonstrating how to use a sharpening stone to raise money for a charity.

But it's not just technique that matters. From the outside, a sharpening stone is a sharpening stone, and they all sharpen knives. But not all of them do it to the same degree. There are various materials and grits to consider, and some are better suited to particular types of steel. To help explain the finer details of what, by all appearances, are just smooth rocks, I enlisted the help of Quintin Middleton, bladesmith and owner of Middleton Made Knives, a South Carolina-based knife company. Then, I put the top-selling sharpening stones—some ceramic, some synthetic, and others diamond—to work by sharpening intentionally dulled knives to see how well and how easily they brought the edge back from ruin. 

While I—and the rest of the staff at Serious Eats—recommend whetstones as the best method for sharpening knives, I understand that not every cook has the desire or interest to learn how to use one. Electric and manual sharpeners are more approachable for the average home cook, and many people choose to use them out of ease and convenience. As with whetstones, there are varying degrees of quality across the electric and manual knife sharpener spectrum. So, in the interest of providing the most complete recommendations possible, I tested a whole bunch of those, too.

The Winners, at a Glance

The Best Whetstone

Shapton Ha No Kuromaku Ceramic Whetstone Set

$108 at Amazon View on Woodcraft.com View on Hocho-knife.com

Yes, I'm leading off with an expensive set, but these two whetstones from Shapton are a near-perfect combination of grits. They brought the blade very close to the factory-finished edge on stainless steel knives and did a respectable job on carbon knives, too. This set comes with protective, ventilated plastic cases that double as stands for the blocks to keep them elevated while you work.

The Best Whetstone for Carbon Steel Knives

Amazon Basics Whetstone

$27 $21 at Amazon

The Amazon Basics Whetstone was the best performer at sharpening carbon steel knives, and it scored almost equally well with stainless blades, too. This stone comes with a wooden stand, a silicone base to hold the stone on the stand, and an angle guide (a very useful tool).

The Best Budget-Friendly Whetstone

Royal Craft Wood 1000/6000 Grit Whetstone Kit

$17 at Amazon $32 at Walmart $27 at Royalcraftwood.com

This value-priced sharpening kit scored just under the Amazon Basics for stainless steel and carbon blades. It’s a simple, two-sided stone with a wooden stand and silicone base that did an exceptional job compared to higher-priced stones.

The Best Electric Knife Sharpener

Work Sharp Ken Onion Knife Sharpener

$140 $105 at Amazon

I shy away from recommending electric sharpeners for reasons I'll expand on later (I promise!), but this model from Work Sharp gave amazing results. It comes with clear instructions and safeguards to prevent damaging your blades.

The Best Electric Knife Sharpener for Beginners

Chef’sChoice 1520 AngleSelect Professional Electric Knife Sharpener

$190 at Amazon $160 at Williams Sonoma View on Chefschoice.com

This sharpener from Chef’s Choice is a good option for those who are timid about knife sharpening but realize the importance of keeping their knives sharp. The 1520 had a minimal learning curve and gave knives a better-than-factory edge. 

The Best Manual Knife Sharpener (If You Must)

ZWILLING J.A. Henckels 4-Stage Pull Through Knife Sharpener

$44 $25 at Amazon View on Zwilling.com $27 at Lowe's

Pull-through sharpeners rank below electric sharpeners in my recommendations owing to their tendency to damage blades. Still, this offering from Zwilling provided the easiest means of achieving a sharp knife.

The Tests

To no one's surprise (ha), the majority of my testing focused on whetstones, so I'll discuss my methodology for that first. To rate each knife’s sharpness, I used a professional edge tester that measures the force in grams necessary to slice through a thread, which I’ll refer to throughout this review as the BESS reading. I then tested the sharpeners using Henckels Solution 8-Inch Chef’s Knives and the whetstones with 8-inch stainless steel chef’s knives and carbon steel petty knives.

• Dulling and Sharpening Test: I dulled brand-new stainless steel chef’s knives and high-carbon petty knives by making 10 slicing strokes across a coarse whetstone. This action was the equivalent of attempting to cut through a brick, to be honest, and the blades were sufficiently dulled. I then measured the sharpness of the dulled knives using a professional blade edge tester. Afterward, I sharpened the dulled knives, starting with the coarsest grit, giving each knife 50 strokes on each side of the blade before repeating the process on the next smoothest grit. Then, I re-tested the sharpness. As the dulled blades didn’t start at a uniform point, it wouldn’t be a valid test only to measure the final result. To address this, I looked at the percentage of change in sharpness from the starting point to the end. I also re-ran the test if the differences were very low, or worse, negative, and kept the best set of scores. 

• Slicing Vegetables Test: After sharpening the knives, I attempted to slice a tomato as thinly as possible and chop a carrot. I looked at the thickness of the slice, the evenness of the slice, and the amount of effort required to complete the slice. 
• Manual and Electric Sharpeners Test: For each of these sharpeners, since they are more direct and coarser than a whetstone, I set the sharpener at a 20-degree angle (if applicable) and drew the knife through the sharpener 10 times per side. I moved to the next-highest grit (or fineness) and repeated the process, using five passes per side, then moved on to the next higher grit. I tested the sharpness on the meter, and any knife that hadn’t achieved 350 grams or lower went back onto the sharpener at the finest grit for five more passes per side. I repeated the slicing vegetables test and evaluated the knives according to that metric.
  

What We Learned

Whetstones vs. Electric and Manual Sharpeners

Before I dive into my findings, here's a quick (okay, quick-ish) primer on the differences between whetstones and electric and manual sharpeners.

• A whetstone—or sharpening stone—is the most low-tech option for sharpening knives. It also gives you the most control and requires the most skill. (Remember here that practice makes perfect...) To use a whetstone, the knife is run across the surface of a damp stone. A minimal amount of the knife's edge is removed—even on coarser stones—so this is ultimately the best for your knife's longevity.
• An electric knife sharpener is a solid option for cooks nervous about using a whetstone. In these models, motorized wheels or belts do the work for you—they're what moves, not the knife. Although electric sharpeners tend to grind away more of the knife's edge than whetstones, they have a lower risk than pull-through sharpeners of scratching and nicking the knife.
• In the case of a manual or pull-through sharpener, you pull the blade across a stationary abrasive. This doesn't offer the most efficient route to super sharp blades, and it's prone to damaging knives. I don't recommend using a pull-through sharpener for your favorite knives.

Why We Don't Typically Recommend Electric Sharpeners

Simply put, an electric sharpener is a blunt tool. As Kenji has said, "Sharpen your knife [with an electric sharpener] a dozen times, and you've lost a good half-centimeter of width, throwing it off balance, and rendering any blade with a bolster (i.e. most high-end forged blades) useless." Naturally, this means you'll have to replace your knives at least every couple of years. If you work with inexpensive knives or don't mind the cost, by all means, grind away.

But there's another reason we prefer whetstones: They are more effective. Even the best electric sharpeners can't get your blades as sharp as a properly-used whetstone.

The Grit of a Whetstone Was (Very) Important

As mentioned above, I used a blade edge tester to measure the sharpness of the dulled knives’ blades. The device measures the grams of pressure one exerts to cut through a piece of thread. Most brand-new knives typically measure between 250 and 350 grams (razor utility knives average 150 to 250 grams, for comparison purposes).

A knife dulls because the edge is no longer straight and has rolled over to one side. For the obsessive (like me), a knife requires resharpening when it reaches 400 grams, but it’s still usable up to about 800 grams. Anything 900 grams or higher shows a significantly rolled edge, and anything over 1,200 grams requires some dedicated work to reset the blade’s angle. Sadly, most folks’ home kitchen knives are in this higher range, but there’s hope for your blade. Here's the mic drop moment/justification for my preference for sharpening stones: The proper grit on a whetstone makes the task of getting a sharpened edge much easier.

A whetstone with a lower-numbered grit (like 800) is coarser and does the heavy lifting for you when sharpening a knife, setting the bevel, and raising a burr. (The bevel is the cutting angle of the blade, and when sharpening one side of the knife, the edge will roll over a little bit to the other side. That’s the burr, and when it develops, it’s time to turn the knife over and sharpen the other side.) Higher-numbered grits (like 3000), which are smoother, take that mostly sharp knife from the first step and refine the edge.

According to Middleton, when sharpening your knife, you should start with 800 or 1,000 grit (anything lower is for repairing the blade), then move to a higher number once you’ve established the edge—the knife should slice a sheet of paper (or a squishy tomato) cleanly and smoothly at this point. You can eventually achieve a sharp knife by working with a medium or fine stone (3,000 grit or higher), but the time commitment will be much longer to reach the results you’d get from starting with a coarser one. If you just need to touch up your blade and not fully sharpen it, you can begin with a finer grit with no worries.

Soaking a Whetstone

Think of sharpening a knife like sanding wood. A fair amount of grit will result from sharpening, and since we’re dealing with steel and stone instead of wood, water provides the lubrication necessary to prevent that grit from building up on your stone. (A related family of sharpening stones relies on oil for lubrication, but I didn’t include those in my tests.) That slurry of metal shavings and stone particles has a benefit in sharpening, too. The particles suspended in the slurry work with the particles on the stone, shortening the time required to sharpen your knife.

The most common way to accomplish this is soaking the stone, typically 10 to 15 minutes, but that’s not the case for all whetstones. According to Middleton, the difference between a stone that requires soaking and a stone that only needs a few drops of water before use is the porousness of the stone’s material. You’ll see bubbles rising from the water when you soak a porous stone as the water thoroughly penetrates the spaces between the grit. I tested both kinds of stones in this review. Some stones come with a “dressing stone” intended to clean the whetstone after use to eliminate any slurry buildup, prolong the whetstone's life, and help prevent bows and divots in them.

Some Whetstones Were Better than Others for Stainless or Carbon Steel

When I compared percentages of increase in sharpness for stainless and carbon steel, I found some disparities. Despite carbon being easier to sharpen than stainless, some stones sharpened stainless about 25% better than carbon, while other stones had the carbon increasing 34% more on the sharpness scale than stainless. Still, others performed about the same for either metal. Considering that information, it’s best to choose a whetstone based on what’s in your knife drawer.

Elevation Was a Good Thing for Whetstones

All of the stones had a stand, whether it was an additional piece or a case that did double duty. Elevating the stone off the counter made it easier to attain a proper angle for sharpening and saved my knuckles from bouncing off the counter’s edge. Not all stands are equal, though. It’s good to look for one with a non-slip surface on the bottom and a wide, heavy base. Lighter-weight or smooth bases jiggled, slid, and sometimes, flipped over, like the Diamond Machining Technology DuoSharp Bench Stone.

How to Use a Whetstone

To properly use a whetstone, keep your focus on the angle of your knife. As Kenji explains in this thorough guide, you want to situate your blade at a 15- to 20-degree angle. Professional cooks can often settle into that sweet spot by feel, but if you're unsure (and many cooks are!), an angle guide is a great helper.

Most sharpening stones should be soaked in water before use: Dry stones can cause damage to your knife. (That said, my top pick, the Shapton required just a few drops of water). Once your stone is saturated, slowly drag the edge of your knife—at that proper angle!—across the stone from heel to tip. Keep a confident, firm but gentle pressure on the knife the whole way through. You'll finish the stroke with the knife's tip on the stone, then repeat until the edge is sharp; ideally around 30 times. If you're working with a double-bevel knife, turn it over and repeat on the other side.

Always start with the coarsest stone (or side of the stone). Repeat the entire process on the fine-grit stone once you've completed the first round, then rinse and dry the knife before testing it for sharpness.

How to Know If Your Electric or Manual Sharpener Is Good

Look for knife sharpeners that have a moderate grit, and, ideally, an electric mechanism. Mechanical sharpeners are typically way too coarse. Manual or electric sharpeners list their coarseness in microns, and the number is often disturbingly low—above 30µ. This degree of coarseness affects the knife’s longevity by unnecessarily removing metal and weakening the edge. In the case of high-speed electrical sharpeners with overly coarse abrasives, it’ll ruin the edge's temper. Changing the tempering (in other words, brittleness) of the blade leads to a vicious cycle, as the edge is now more susceptible to damage that requires grinding to repair.  

This is also why we prefer electric sharpeners, like the Ken Onion Work Sharp, over pull-through sharpeners. When cooks have to choose how much pressure to apply as they glide the knife through, they often press much too hard, nicking and damaging the blade in the process.

The Criteria: What to Look for in a Knife Sharpener

A good whetstone should have a sturdy stand, which makes it easier to attain a proper sharpening angle. It’s best to buy a whetstone with a 1,000 grit stone (a baseline minimum) and a fine grit stone of 5,000-6,000 (for giving the knife a fine finish) to achieve the best results. An electric sharpener should have moderate coarseness and a moderate speed that will minimize damage to the blades.

Our Favorite Whetstones and Knife Sharpeners

The Best Whetstone

Shapton Ha No Kuromaku Ceramic Whetstone Set

$108 at Amazon View on Woodcraft.com View on Hocho-knife.com

What we liked: The Shapton stones were color-coded for easy identification (orange for 1,000 grit and pink for 5,000 grit), and they didn’t require soaking. I just opened the box, placed the stone on top of the box/base, and rubbed a few drops of water on it—then it was time to sharpen. The stones gave the best performance for stainless blades, bringing them from dull to an almost factory finish (although the stones weren’t too shabby with carbon steel, either). Both knives cut thin, even, transparent slices of tomato after sharpening, which set the bar high for subsequent sharpeners.

What we didn’t like: The stones were easy to use, effective, and didn’t require soaking, so finding fault in them is splitting hairs (with an extremely sharp blade) at this point. The fact that there were two stones could be bothersome to those who habitually lose vital pieces of sets (like me), and the plastic cases that serve as stands don’t have much traction, so I had to put a towel under them to keep them steady. The performance justifies the higher price tag but is still a hefty cost.

Key Specs

• Grits: 1,000/5,000
• Material: Ceramic
• Dimensions: 8.25 x 2.75 x .75 Inches
• What’s included: 2 stones, 2 plastic cases that double as stands
• Good for stainless steel: Yes
• Good for carbon steel: Yes
• Requires soaking: No
• Cleaning and care: Rinse briefly and scrub with a soft brush if necessary to remove grit, dry thoroughly

The Best Whetstone for Carbon Steel Knives

Amazon Basics Whetstone

$27 $21 at Amazon

What we liked: I didn’t have high hopes for an Amazon-brand product, but this stone did the best at sharpening carbon steel knives, taking them from 945 grams to factory-sharp. While this model shone in the carbon arena, it was also no slouch when sharpening stainless blades. There was a 73% improvement in sharpness when put through its paces. It’s a single, reversible stone (one side is 1000 grit, the other 6000 grit) that comes with a form-fitting silicone base that holds it firmly atop the wooden stand. 

What we didn’t like: The stone is slightly soft, which could lead to chips and damage, and the white 6,000-grit side shows visible grit buildup on the stone, even after scrubbing with a brush. A dressing stone might be in order to keep this stone at its best potential. 

Key Specs

• Grit: 1,000/6,000
• Material: Ceramic
• Dimensions: 7 x 2.5 x 1.25 inches
• What’s included: Dual-sided stone, wooden stand, silicone base, angle guide
• Good for stainless steel: Yes
• Good for carbon steel: Yes
• Requires soaking: Yes, 10 minutes
• Cleaning and care: Rinse briefly and scrub with a soft brush if necessary to remove grit, dry thoroughly, and then air dry

The Best Budget-Friendly Whetstone

Royal Craft Wood 1000/6000 Grit Whetstone Kit

$17 at Amazon $32 at Walmart $27 at Royalcraftwood.com

What we liked: This stone gave great results for carbon and stainless steel knives, only falling short of my top pick by less than two percentage points. It’s a safe assumption that a few more strokes on each side for each grit would have put it on par for a fraction of the price. These aren’t the expected results from a “value” stone. Indeed, I found it the best performance-to-dollar whetstone I tested.

What we didn’t like: This stone is prone to chipping and suffered some damage during testing. The knives I sharpened with the Royal Craft Wood cut tomatoes into transparent slices, though they did fall apart.

Key Specs

• Grit: 1,000/6,000
• Material: Ceramic
• Dimensions: 7.25 x 2.5 x 1 Inches
• What’s included: Dual-sided block, silicon base, wood stand, angle guide
• Good for stainless steel: Yes
• Good for carbon steel: Yes
• Requires soaking: Yes, 10-12 minutes
• Cleaning and Care: Rinse briefly and scrub with a soft brush if necessary to remove grit, dry thoroughly, and then air dry

The Best Electric Knife Sharpener

Work Sharp Ken Onion Knife Sharpener

$140 $105 at Amazon

What we liked: This model from Work Sharp is the only electric sharpener Serious Eats has recommended in the past. Named for knife designer Ken Onion, it resembles a belt sander more closely than a sharpener on a tabletop, sitting on four non-skid rubber feet. The lengthy instruction manual describes the sharpening process for any number of blade shapes and types, including serrated, straight blades, scissors, mower blades, and any number of outdoor specialty knives. The blade guide has settings for angles between 15 and 30 degrees in five-degree increments, and the power switch has a variable-speed dial control. The sharpening happens by drawing the blade through the guide across a spinning abrasive belt. 

So how did it perform? After wrestling with mounting the belts, the blade tested 300 grams on the BESS scale, which is equivalent to factory-sharp. There were no burrs or micro-serrations on the blade. This sharpener was the gentlest on blades of all the electric models I tested.

What we didn’t like: While the Work Sharp was easy to use while sharpening, setting it up took some wrangling. The knife’s edge had no apparent burrs or micro-serrations, but there were striations on the blade, which would steer me away from using this sharpener for Damascus steel or finely-polished Japanese steel knives.

Key Specs:

• Dimensions: 10 x 5.5 x 6 inches
• Grits: 120/220/1,000/3,000/6,000
• Sharpening material: Diamond/composite

The Best Electric Knife Sharpener for Beginners

Chef’sChoice 1520 AngleSelect Professional Electric Knife Sharpener

$190 at Amazon $160 at Williams Sonoma View on Chefschoice.com

What we liked: This sharpener was quick and easy to use. A few draws of the knife gave tactile feedback when moving the blade across the sharpener at the proper speed and pressure. There were blade guides for 15- and 20-degree angles to accommodate Japanese and Western-style blades, and for the daring, there were instructions for changing the blade’s bevel from Western to Japanese style. However, that’s not an endorsement from me due to the amount of steel that process would remove. 

I'll remind you here I'm not a fan of electric sharpeners due to the amount of metal they remove from the knife. That said, the learning curve for a whetstone may be daunting to some, and if the choice lies between a mechanical sharpener and a dull knife, I'll advocate for electric sharpeners like this one.

After one trip through the sharpener, the knife showed 150 grams on the edge tester, equivalent to a box cutter blade. No chips or micro-serrations were visible, and the sharpness results, combined with the ease of use, set this sharpener apart.

What we didn’t like: There were fine scratches after sharpening, and the knife’s tip showed some rounding. There was no pressure control or indicator, so learning the speed and pressure necessary to sharpen a blade was based on feel and auditory feedback from the sharpener. Given the scratches and the easily attained potential for over-grinding, this was not a sharpener to use on expensive knives, family heirlooms, or Damascus steel. 

Key Specs:

• Dimensions: 4.25 x 9.75 x 4.25 inches
• Grit: Coarse/polishing
• Sharpening material: Diamond-coated steel

The Best Manual Knife Sharpener (If You Must)

ZWILLING J.A. Henckels 4-Stage Pull Through Knife Sharpener

$44 $25 at Amazon View on Zwilling.com $27 at Lowe's

What we liked: This sharpener style is small, compact, and easy to store, which lends to its popularity. It was a simple sharpener, with a padded rubber bottom, comfortable hand grip, and fine and coarse slots for “Asian” or “Standard” blades. Drawing the blade through each side for the requisite amount of strokes per my tests yielded “new blade sharp” results at 271 grams after a second round of fine-grit sharpening. 

What we didn’t like: The sharpener's angle grooves accommodate a range of blade thicknesses, which puts the fine-tuning of the proper angle squarely on the user. With the possibility of that angle variance, the ZWILLING could dull knives as easily as it sharpens them. Also, the sharpener's design made it difficult to focus on the tip, which is a vital part of filleting and boning knives.

Key Specs:

• Dimensions: 7.5 x 10.5 x 1.75 inches
• Grit: Coarse/fine
• Sharpening Material: Ceramic

The Competition

• KING Whetstone Starter Set: This is a great set for beginners, and it restored both stainless steel and carbon blades to factory-sharp levels. A thin silicone-like ring around the middle of the stone where the coarse and fine sides meet helps hold the stone in place on the stand. It’s a perfectly fine stone, but it didn’t quite keep up with the winners in that department. It scored high with carbon knives but dragged a little behind with stainless steel.
• Cangshan 7-Piece Kitchen Knife Care & Sharpening Kit: This is another good set for beginners in that it performed well with little effort; the stones formed a proper slurry quickly, and after around 25 runs of a blade, knives emerged sharp enough to cleave through rubbery tomato skin easily. The only real drawback is the stone’s size, which a more experienced user might find too small to sharpen an eight-inch blade easily.
• Naniwa Chosera 3,000 Grit Stone: Given that this is a single-grit stone, I altered the test to give 100 strokes per side and saw my fourth-best improvement in sharpness and decent tomato-cutting results. At the price, I'd like to see a better return for time spent.
• Kitayama Combo Stone: The Kitayama didn’t show as much of a sharpness increase as other similar stones, and I have to think that the 4,000 grit fine side, as opposed to the more common 5,000 or 6,000 grits, is why. 
• Chefic Sharpening Stone Whetstone Knife Sharpener Stone: This stone’s 3,000/8,000 grit combination did much better with softer carbon steel than with stainless steel, which saw only a tiny sharpness increase. The 3,000-grit starting point may be too low for dull stainless steel.
• Sharp Pebble Premium Whetstone: Despite this stone’s 1,000/6,000 grit combination, I saw very slight (sub-6%) improvement on stainless steel blades and only about 30% with carbon after multiple tests.
• Diamond Machining Technology DuoSharp Bench Stone: The DuoSharp was clumsy to use. It was top-heavy and flipped over twice during testing. It’s the only stone that saw negative sharpness improvement on stainless steel across multiple tests, although it had better results with carbon steel blades.
• Chef’sChoice Rechargeable AngleSelect Electric Sharpener: This is the wireless version of the winning Chef'sChoice AngleSelect Professional Electric Knife Sharpener. I found the listed battery life of 45 minutes started affecting performance as the charge drained at 30-35 minutes. I expected a similar performance to the regular AngleSelect, but found scratches down the blade and a duller edge, even after a second round of sharpening.
• Brentwood TS-1001 2-Stage Electric Knife Sharpener: The Brentwood only sharpened at a 20-degree angle and didn’t quite get that job done. The blade only reached 467 grams, with scratches along its length.
• Smith’s Deluxe Diamond Electric Knife Sharpener: This is a beginner-friendly electric model, but don’t use it on knives you value. The sharpening results were reasonable, but the sharpener left the sides of the knife with scratches and striations.
• Secura Electric Knife Sharpener: The Secura sharpener didn’t deliver great results, but did cause micro-serration damage to the blade. Vague instructions, no indication of sharpening angles, wobble in the guide slots, and mediocre results took the Secura’s rating way down.
• Narcissus Professional 2-Stage Electric Knife Sharpener: Although it’s easy to use, I saw negative sharpening and blade damage after testing this sharpener, and I can’t recommend it.
• Mueller UltraSharp Diamond 4-Stage Manual Knife Sharpener: This diamond pull-through hand sharpener has slots for scissors and three graduating levels of coarseness for knife sharpening. It performed surprisingly well, bringing the blade to factory-sharp levels. If price is a consideration, the Mueller is a great value sharpener.
• KITCHELLENCE 4-in-1 Knife Sharpener: This pull-through manual sharpener has three (curiously, not four) sharpening slots. The first is ceramic and gentler on blades, followed by two tungsten slots for refinement that remove more metal from the blade. It was easy to use and got the blade factory-sharp without significant damage to the blade. Although it performed just fine, “just fine” is about all I can say about it—it didn’t set itself apart from the crowd in any way.
• Cangshan SHARK Series 4-Stage Knife Sharpener: This pull-through manual sharpener is actually a two-stage, with two slots each for Japanese and Western-style blades. The coarse slots for both types utilize tungsten, while the fine slots use a gentler ceramic rod. The sharpening results were middle-of-the-road for improvement, and there were visible microchips and serrations on the blade’s edge.
• Material Kitchen The Sharpener: This is a no-nonsense, easy-to-use sharpener with a single slot for sharpening. It’s small enough for traveling, and it restored the blade to factory sharpness, although there were some rough spots on the side of the knife.
• Messermeister Pull-Through Sharpener: This two-slot sharpener uses diamond and ceramic wheels for coarse and fine sharpening. It’s very easy to use and cut the knife’s dullness by half, but it still had a pretty middling BESS score. The manufacturer’s website warns that it may leave scratches during sharpening, so take that into consideration. 
• RAZORSHARP™ Knife Sharpener with Adjustable Angle Guide: This is a pull-though manual sharpener with adjustable angles from 16 to 24 degrees to accommodate kitchen knives, outdoor knives, and cleavers. The diamond-coated ceramic sharpening tips did a respectable job of sharpening the blade to the outer realm of factory sharpness.
• Miyabi 2-Stage Diamond/Ceramic Handheld Knife Sharpener: This two-stage manual pull-through sharpener has a clear plastic cover over the sharpening wheels, allowing you to see the process in a purely aesthetic way. It does nothing to improve the process, ultimately lending handheld pencil sharpener vibes. When I didn’t achieve the sharpness threshold in the first round of testing, I ran it through a second sharpening, which achieved negative results, losing about 80 points on the BESS scale.
• Sharp Pebble Orange Ninja 4-Stage Knife Sharpener: This handheld pull-through sharpener has three coarseness settings for straight knives and a fourth for serrated blades. I encountered problems with the coarse setting, where the blade “skipped and galloped” across the sharpener, leaving a scalloped section of the blade where it removed too much metal. The BESS rating was impressive, in the utility knife range, but the damage to the blade was a deal breaker.
• Wüsthof Universal Hand-Held Knife Sharpener: This pull-through manual sharpener has slots for Japanese and Western-style blades, with coarse carbide and fine ceramic sharpeners for each type. A recurring theme with some pull-throughs is the inability to provide even pressure past the midway point of the blade to the tip due to the angle at which one pulls the knife. Even after a second round of sharpening, I never reached the target BESS score of below 350 grams.
• Tumbler Orginal Diamond Rolling Knife Sharpener Set: Tumbler makes a good set for people who don’t want to commit to a sharpening stone or electric sharpener but want better results than most pull-throughs. The knife magnetically attaches to their block at a preset angle, and you roll the sharpener back and forth. There’s a little metal loss, but no more than with a whetstone. The knife tip was difficult to sharpen as the sharpening cylinder flexed it slightly.
• HORL 2 Rolling Knife Sharpener: The HORL shares a design similar to that of the Tumbler. It’s a wooden block with pre-set angles and magnets to hold the knife in place while you roll the abrasive cylinder along the length of the blade. The HORL features a diamond sharpening and ceramic finishing sides of the cylinder. The BESS score came in just over the acceptable testing threshold, which detracts from the price justification.
• Work Sharp Rolling Knife Sharpener: The Work Sharp is a variation on a theme from other rolling sharpeners. The four-sided block has 15-, 17-, 20-, and 25-degree angles for a wide range of knives, and the cylinder has interchangeable coarseness disks. The cylinder was difficult to control, leaving the tip duller than the bulk of the body, and the overall results were pretty disappointing, with a 543-gram BESS score and chips in the blade that were noticeable by touch. 

FAQs

What’s the difference between an electric knife sharpener and a whetstone?

Electric knife sharpeners work by grinding away at the metal of your blade; they're much more harsh than a whetstone. Corey Milligan, founder of New West KnifeWorks in Jackson, WY, doesn’t pull punches when it comes to his opinion of electric sharpeners, “As someone who makes knives with a lifetime guarantee that I want to last 100 years, it scares me very much about how much metal gets taken away when you use an electric sharpener.” Another scary factor is that grinding generates a significant amount of heat, which can ruin the edge’s temper. The heat isn’t enough to affect the whole blade, but the edge can weaken enough that it’s susceptible to chipping and pitting.

While electric sharpeners are fast and convenient, that speed comes from quickly grinding the blade to the proper angle, removing more metal in the process than other, slower methods. Whetstones are gentler on the blade due to the slower motion across the stone, removing significantly less metal to set the knife’s edge. Grinding smaller amounts of metal extends the longevity of the blade, so if you want to keep your expensive knives around for the duration, a whetstone is the clear winner.

Can you use a whetstone for single-beveled knives? Or carbon steel blades?

The answer to both of these questions is yes. With a single-beveled knife, you’ll only sharpen the angled side of the blade. However, in doing that, you’ll raise a slight burr on the “straight” side of the blade that you’ll need to deal with. Experts recommend a 9-1 or 10-1 ratio of strokes on the beveled edge and flat edge, meaning you’ll turn the knife over and give one stroke on the straight edge for every nine or ten strokes on the beveled edge. 

Regarding carbon steel blades, Middleton says they have fewer ingredients in the metal than stainless steel. That makes the steel softer, making carbon blades easier to sharpen on a whetstone. 

Do you need to soak a whetstone?

Not all whetstones require soaking. Middleton explains that water lubricates the knife and the stone, keeping the resulting grit derived from grinding the knife against the stone from settling into the stone or damaging the blade. Stones are made of varying materials, some more porous than others. The more porous stones require soaking to retain enough water to provide the necessary lubrication, while other stones function just fine with a few drops of water on the surface. Always check the manufacturer’s recommendations on soaking or not to avoid damaging your stone or knife.

How often should you sharpen your knives?

Milligan uses a tomato as a baseline sharpness detector. If your knife no longer slices a tomato easily, it’s time to sharpen it. From there, he gets more specific, saying he cooks often and has a favorite knife he uses almost daily. With that level of use, he recommends learning how to sharpen and then sharpen the knife monthly. 

Where can you get your knives professionally sharpened?

Milligan recommends searching for a local sharpening business as your first choice. A query in my area gave about 20 results, some of them in unexpected places, like lawnmower repair shops. But think about it: a lawnmower blade requires periodic sharpening, right? The next choice is to ship them off to a service. Milligan warns in both cases to start with knives you don’t have a deep attachment to. Little permanent damage results from a company sharpening them on a stone, but if they use mechanical sharpeners, you could run into trouble due to the amount of metal they remove. While building a rapport with a sharpening company, start with a knife you don’t care much about and trace its outline on paper before entrusting it to a new company. When you get your knife back, place the knife on the outline, and you can see if they’ve removed an excess amount of metal. “My biggest concern with sharpening is grinding away lifetimes out of the blade,” he says. Finally, some knife manufacturers, like Milligan’s company, offer lifetime sharpening services by mail or in-store. 

Can you sharpen ceramic knives yourself?

Ceramic knives are more prone to chipping, so it takes a bit more finesse and caution when sharpening them at home. Importantly, you can't use a traditional whetstone to sharpen a ceramic knife—you need something more abrasive, like a diamond sharpener.

Why We’re the Experts

• Greg Baker is a former chef with multiple James Beard nominations from Tampa, Florida.
• He’s written several reviews, including charcoal chimneys and vacuum sealers, for Serious Eats. 
• For this piece, he interviewed Corey Milligan, founder of New West KnifeWorks, and Quintin Middleton, owner and knife maker of Middleton Made Knives, to gain their insight into how sharpeners affect steel and the best practices for sharpening knives.