Pull-through, whetstone or electric: how to choose a knife sharpener

A dull knife is harder to control and more likely to slip. The fix depends on whether the edge is just bent out of line or genuinely worn down, and on what kind of knives you own.

Honing vs. sharpening

• Honing realigns an edge that has rolled or bent with use. It removes little or no metal. A honing rod (often called a "sharpening steel") does this, and a few strokes before cooking keeps a knife feeling sharp longer.
• Sharpening grinds away metal to create a new edge. You need it when honing no longer brings the edge back.

Many people who think they need a sharpener actually need a honing rod used regularly, plus a real sharpening a few times a year.

The main types

Type	Best for	Trade-offs
Manual pull-through	Quick, easy touch-ups on everyday Western knives	Fixed angle; coarse slots can remove a lot of metal and leave a rough edge
Electric	Fast, consistent results with little skill	Removes metal quickly; can shorten a blade's life if overused; bulkier
Whetstone	The best edge and full control, on any knife	Takes practice and time; needs soaking or wetting; needs flattening over time
Guided systems	Whetstone-quality edges with a clamp or guide holding the angle	More expensive and slower to set up
Honing rod (steel or ceramic)	Daily maintenance between sharpenings	Doesn't fix a truly dull edge

The angle question

Knives are sharpened to an angle on each side of the blade.

• Many Western-style knives have edges of around 20 degrees per side.
• Many Japanese-style knives have finer edges, often around 15 degrees per side, made from harder steel.

Check what your knife maker recommends. Some pull-through and electric sharpeners have slots for both angles; others are set to one. Sharpening a fine Japanese edge at a much wider angle changes how the knife cuts.

Harder, thinner Japanese steels can also chip on aggressive sharpeners. That's why many owners of these knives prefer whetstones or sharpeners specifically designed for them.

Grits, in plain terms

Sharpening surfaces are graded by grit. Lower numbers are coarser and remove metal faster; higher numbers polish the edge.

• Coarse (low hundreds): repairs chips and very dull edges.
• Medium (around 1000): the main sharpening grit for most knives.
• Fine (several thousand): refines and polishes the edge.

A combination stone with a medium and a fine side is a common starting point for whetstones.

Serrated knives

Bread knives and other serrated blades can't be sharpened in most standard slots. Look for a sharpener that specifically says it handles serrated edges, or use a tapered rod that fits the serrations. Serrated knives also stay usable longer between sharpenings.

Safety and practical details

• Stable base. A pull-through or electric sharpener should sit firmly on the counter, ideally with a non-slip bottom.
• Hand guard on handheld models.
• Clean-up. Metal filings collect inside electric sharpeners; check how to empty them.
• Test the edge carefully on paper or a tomato rather than your finger.

Questions people ask

How often should I sharpen my kitchen knives?

It depends on use and steel. Many home cooks hone weekly or before each use and sharpen a few times a year.

Do pull-through sharpeners ruin knives?

They can wear a blade faster, especially coarse carbide slots used often or with heavy pressure. Used lightly on everyday knives, they're a practical option.

Is ceramic or steel better for a honing rod?

Ceramic rods are slightly abrasive and work well on harder steels; smooth steel rods only realign. Many people prefer ceramic for a mixed knife collection.