America's Test Kitchen Knife Sharpener: What ATK Tests and Recommends

America's Test Kitchen has tested knife sharpeners more rigorously than almost any other publication. If you're searching for their knife sharpener recommendations, here's the quick answer: ATK has consistently recommended electric sharpeners from Chef'sChoice, particularly the Chef'sChoice Trizor XV and the 4643, as well as pull-through sharpeners like the KitchenIQ Edge Grip for budget buyers. Their testing methodology looks at both restored sharpness and long-term blade preservation, which produces more nuanced results than tests that only measure initial sharpness.

This article covers ATK's testing approach, their top picks across sharpener types, and what their findings actually mean for choosing the right sharpener for your knives.

How America's Test Kitchen Tests Knife Sharpeners

ATK's testing is unusually thorough compared to most reviews. Their methodology for knife sharpeners typically involves:

Baseline sharpness testing: They deliberately dull test knives through standardized use before sharpening, so they're measuring improvement rather than just testing an already-sharp blade.

Multi-knife testing: They run the same sharpener on multiple knife types: Western German knives (Wusthof, Henckels), Japanese knives (various brands), and budget stamped knives. A sharpener that works well on German steel but damages Japanese steel doesn't get a full recommendation.

Long-term blade preservation: This is where ATK's testing gets more sophisticated than most. They measure how much metal each sharpener removes per pass, because aggressive sharpeners restore sharpness faster but consume blade material faster. A sharpener that removes 1mm of metal per use will wear a knife to a stub in 10 years of regular use.

Follow-up testing: ATK tracks whether sharpened knives hold their edges over subsequent testing days, not just immediately after sharpening.

What This Tells You

ATK's concern about metal removal explains why they often recommend more expensive electric sharpeners over aggressive pull-through models. Cheap pull-through sharpeners can sharpen a knife in 10 seconds, but they remove so much metal that you're essentially shortening your knife's lifespan dramatically.

For quality knives (anything over $50), the metal removal rate matters. For cheap stamped knives you'll replace in 3-4 years anyway, an aggressive pull-through sharpener is fine.

ATK's Top Electric Knife Sharpener: Chef'sChoice Trizor XV

The Chef'sChoice Trizor XV has been ATK's top-recommended electric sharpener for years. It's a three-stage electric sharpener that both sharpens and converts knives to a 15-degree edge angle (down from the 20-degree angle most Western knives come with from the factory). The sharper angle improves cutting performance at the cost of some edge durability.

At $160-$180, it's an investment, but ATK's testing shows it removes less metal per sharpening session than cheaper alternatives while producing a consistently excellent edge.

Three-stage process (abrasive grinding, honing, stropping) produces a multi-faceted edge that cuts cleanly
Diamond abrasives in stage 1 sharpen efficiently without gouging
Stropping stage 3 polishes the final edge to a fine working sharpness
Consistent results across multiple knife types and steel hardnesses
Works on both Western 20-degree knives and Japanese 15-degree knives (you use different slots)

The practical benefit of the 15-degree conversion is real for home cooks. A 15-degree edge is noticeably sharper for food prep tasks like slicing tomatoes, breaking down chicken, and fine herb work.

For a comparison of how sharp knives perform in cooking, the America's Test Kitchen best knives guide covers their top picks across knife categories.

ATK's Budget Pick: KitchenIQ Edge Grip

For buyers who want a functional sharpener without spending $160, ATK has recommended the KitchenIQ Edge Grip pull-through sharpener (around $10-$15) as a budget option. It's a V-shaped carbide/ceramic two-stage pull-through with a suction cup base.

What ATK likes about it: It sharpens effectively and quickly for the price. The carbide slot handles dull or nicked edges. The ceramic slot finishes the edge. The suction cup prevents counter slip during use.

What ATK cautions: The carbide slot removes significant metal per pass. They recommend using only the ceramic finishing slot for regular maintenance and reserving the carbide slot for blades that are genuinely dull, not for routine touch-ups.

For knives that cost less than $50, the KitchenIQ is a fully acceptable solution. For premium knives, use it sparingly.

Pull-Through vs. Electric vs. Whetstone: ATK's Perspective

ATK has tested all three sharpener types extensively, and their view is nuanced rather than dogmatic.

Pull-Through Sharpeners

Pros: Fast, easy to use correctly, no skill required, inexpensive. Cons: Remove significant metal (especially the aggressive carbide slots), less precise edge geometry, less useful for Japanese knives with asymmetric bevels.

ATK recommendation: Fine for budget knives and occasional use on any kitchen knife. Not ideal for regular maintenance of premium knives.

Electric Sharpeners

Pros: Consistent edge geometry, controlled metal removal, handles most knife types, three-stage process produces genuinely good edges. Cons: Expensive, take up counter space, and the best ones (Chef'sChoice) convert 20-degree knives to 15 degrees, which changes the original blade geometry.

ATK recommendation: Best overall for home cooks who want consistent results without learning technique. Chef'sChoice Trizor XV is the specific recommendation.

Whetstones

Pros: Most precise edge, least metal removal per session, can restore any blade, best for Japanese knives with specific edge angles. Cons: Learning curve, time investment, requires consistent technique to produce even results.

ATK recommendation: Preferred by ATK for serious cooks who are willing to learn. A 1000/3000 grit combo stone does everything a home cook needs. Acknowledges the learning curve is a real barrier for most buyers.

For a broader discussion of knife care, the best kitchen knives guide covers maintenance alongside knife selection.

What ATK Says About Sharpening Frequency

A common misunderstanding: sharpening and honing are different, and ATK draws a clear distinction.

Honing straightens the microscopic edge teeth that fold over during cutting. It doesn't remove metal. ATK recommends honing before every major prep session, or at least before any significant cooking day. A smooth honing steel (not a grooved "sharpening" steel) is their preferred tool for this.

Sharpening removes metal to create a new edge. ATK's testing suggests most home cooks need to sharpen their primary knives once or twice a year with regular honing. Cooks who don't hone at all may need to sharpen 3-4 times per year to maintain adequate performance.

The KitchenIQ and similar pull-through sharpeners are sometimes used for "sharpening" weekly, which in ATK's view is over-sharpening that shortens knife life unnecessarily. Their recommendation: hone frequently, sharpen infrequently.

Specific ATK Findings on Japanese vs. German Knife Sharpening

ATK has specifically tested how different sharpeners handle Japanese knives, which are harder (60-62 HRC) and typically ground to 10-15 degrees per side rather than 20 degrees. Their findings:

Standard V-groove pull-through sharpeners (including carbide models) are not suitable for Japanese knives. They're designed for 20-degree Western edge angles and will damage the thinner Japanese bevel.
The Chef'sChoice Trizor XV has a dedicated slot for 15-degree knives that works for most Japanese knives.
For true Japanese knives with asymmetric bevels (single-bevel knives used by professionals), a whetstone is the only appropriate sharpening method.

If you own both German and Japanese knives, ATK's recommendation for a single sharpener that handles both well is the Chef'sChoice Trizor XV, using the appropriate slot for each knife type.

FAQ

What knife sharpener does America's Test Kitchen recommend most? The Chef'sChoice Trizor XV electric sharpener is ATK's top pick for overall performance and blade preservation. For budget buyers, the KitchenIQ Edge Grip pull-through is their recommendation, used carefully with awareness of its aggressive metal removal.

Does ATK recommend whetstones over electric sharpeners? ATK acknowledges whetstones produce the best edges with the least metal removal, but they're realistic about the learning curve. For most home cooks, the Chef'sChoice produces consistently excellent results without requiring practice. They recommend whetstones for cooks willing to invest time in learning the technique.

How often does ATK say you should sharpen your knives? Once or twice a year for a home cook who hones regularly. More frequent sharpening shortens knife life unnecessarily. The more important habit is regular honing, which ATK recommends before every significant prep session.

Does sharpening ruin expensive knives? Aggressive pull-through sharpeners (carbide V-slot models) remove enough metal with each use that they meaningfully shorten a knife's life over years. Electric sharpeners like the Chef'sChoice and whetstones remove far less per session and are safe for long-term knife maintenance.

What to Take Away

ATK's knife sharpener testing is some of the most reliable guidance available on this topic because they evaluate both immediate sharpness and long-term blade impact. Their recommendations are consistent: the Chef'sChoice Trizor XV for buyers who want the best result without learning whetstone technique, the KitchenIQ Edge Grip for budget-conscious buyers who will use it appropriately. Most importantly, hone your knives regularly with a smooth honing steel and you'll sharpen far less often than you think.