The Chef’sChoice Trizor XV produced the keenest and most consistent edges of all the knife sharpeners we tested. And it did so more quickly and reliably than any other sharpener. And because of the design, it’s virtually impossible to make a mistake, even if you’ve never used a knife sharpener before. It repeatedly brought both of our test knives—one of them a $30 German workhorse, the other a $150 Japanese thoroughbred—back from dead dull to razor sharp. Its comprehensive instruction manual explains each step clearly, and its notably sturdy construction suggests that you can expect many years of performance. (We’ve been using one in the Wirecutter test kitchen since 2016.)

Above all, the Trizor XV is our pick because of its ability to dependably return badly dulled knives to an extremely sharp edge. Even after we destroyed the knives’ edges with sandpaper, the Trizor XV repeatedly sharpened both the inexpensive, stamped-steel Wüsthof and the pricey, forged-steel Mac back to factory-new condition—despite their being made of different alloys and having different blade geometry. (Note: XV stands for 15 degrees, the final angle at which the Trizor XV sharpens. Trizor refers to the three progressive facets—rough, medium, and fine—created by the machine’s three sharpening wheels.)

After it was sharpened on the Trizor XV, the same knife slices tomatoes smoothly in one stroke. Video: Michael Murtaugh

Dull knives struggle to cut tomatoes (and anything else), even if you bear down hard and saw. Video: Michael Murtaugh

After it was sharpened on the Trizor XV, the same knife slices tomatoes smoothly in one stroke. Video: Michael Murtaugh

Dull knives struggle to cut tomatoes (and anything else), even if you bear down hard and saw. Video: Michael Murtaugh 1 of 2

Also important, the Trizor XV sharpened the blades evenly from heel to tip, leaving no dull spots. We got uneven sharpening—with the tip not as keen as the rest of the blade—in several tests of the similarly priced Work Sharp Culinary E3, the Trizor’s closest competitor in our trial.

And the Trizor XV sharpens knives fast. From start to finish, it took us a maximum of 4 minutes to bring an 8-inch knife from a sandpaper-dulled state to a like-new edge. Following the instructions, we found that every “pull” of an 8-inch blade through the sharpener took between 5 seconds (on the coarse abrasive) to just 1 or 2 seconds (on the fine “stropping/polishing” abrasive), and the total number of pulls topped out at around 30. By contrast, on the Work Sharp E3, it took at least 5 minutes to sharpen an 8-inch knife, and often longer. The total number of pulls sometimes topped out lower, at around 20, but because every pull took about 8 seconds, when going by the instructions, the total time was greater. And on badly dulled knives, we sometimes ran to 30 pulls, or about 8 minutes. (If you’re running the numbers and coming up short, bear in mind that resetting the blade for each pull, and intermittently testing the edge, adds considerably to the total time elapsed.)

One reason the Trizor XV produces consistently sharp knives is its design, which makes it virtually impossible to mess up the sharpening process. When sharpening by any method, it’s critical to hold the blade at a consistent angle: If you don’t, the result is a rounded-over, dulled edge, rather than a sharp one formed by the apex of two consistent bevels. Like most electric sharpeners, the Trizor XV uses rigid, angled slots to help orient the blade. But it adds a feature that others lack: spring-loaded guides inside the slots that grip the blade at the correct angle and keep it from shifting around during the sharpening process. The Work Sharp E3—again, the nearest competitor in our test—doesn’t have an equivalent mechanism. Instead you have to manually set the blade’s angle in the slot and then manually maintain that angle as you slowly draw the blade through the sharpening element. In our testing, despite taking great care, we found it easy to slip up by starting the blade at the wrong angle or shifting it midstream (because the slot provides wiggle room), or having the blade snag in the slot and skid sideways into the belt. (Details on the E3 appear below, in the Competition section.)

The Trizor XV’s owner’s manual is another of this sharpener’s strong points. Once you’ve used any decent sharpener a few times, you’ve got the hang of it, but the Trizor’s detailed manual helps minimize mistakes from the get-go. By contrast, the manuals from Work Sharp Culinary (for all four models we tested) are more basic and would benefit from additional detail.

Finally, the build quality of the Trizor XV stands out. It’s a heavy, sturdy piece of equipment, weighing 4 pounds, 2 ounces, and equipped with a 125-watt, 2.1-amp motor. The Work Sharp E3 feels lightweight in comparison, at 1 pound, 10 ounces, with an 8.5-watt, 0.7-amp motor. Our 2016 test model Trizor XV has stood up to years of use in the Wirecutter kitchen, and after our formal tests of the 2019 unit were finished, we used it to sharpen more than a dozen staffers’ knives, running it for up to 30 minutes at a time. It’s not cheap, but if you spend a lot of time using your knives in the kitchen, we believe it’s a worthwhile investment. (Note: The third-stage “stropping/polishing” discs will, by design, eventually clog with metal debris from knives; they can be resurfaced with an included mechanism or replaced entirely.)