A whetstone, used at the angle your knife was ground to, sharpens every plain edge in a home kitchen. That is the short answer. A honing rod does not sharpen at all, it straightens an edge that has rolled over. Pull-through and electric sharpeners do genuinely sharpen, and they are a reasonable choice for softer Western stainless, but they remove metal in a fixed pattern that can damage hard Japanese steel, serrated edges, ceramic blades and single-bevel knives. Which group your knife belongs to decides everything that follows.
Why knives go dull, and why honing is not sharpening
An edge fails in two stages. First it rolls: the very thin apex bends to one side under load, so the knife stops biting even though the steel is still there. Then it wears: that apex abrades away, and the knife is blunt in the ordinary sense.
A honing steel, sometimes called a honing rod, fixes the first stage by pushing the rolled apex back into line. It removes almost no metal. Sharpening fixes the second stage by grinding new metal away until a fresh apex forms. This is why a knife can feel restored by honing on Monday and need real sharpening by the end of the month. The two jobs are different, and neither substitutes for the other.
The method-by-knife matrix
This is the part most pages leave out. A method that is routine on one knife is destructive on another.
| Knife type | Whetstone | Pull-through | Electric | Honing rod | Professional |
|---|---|---|---|---|---|
| Western stainless (German-style chef’s knife, X50CrMoV15 and similar) | Safe | Safe | Safe | Safe | Safe |
| Japanese double bevel (santoku, gyuto, VG-10 and harder steels) | Safe | With care | With care | With care, use a ceramic or fine rod | Safe |
| Japanese single bevel (yanagiba, deba, usuba) | Safe, technique specific | Do not | Do not | Do not | Safe |
| Serrated (bread knife, some utility knives) | Do not, not on a flat stone | Do not | Only on a machine with a dedicated serrated slot | Do not | Safe |
| Ceramic | Do not, needs diamond | Do not | Do not, unless diamond and rated for ceramic | Do not | Safe, and usually the only sensible route |
"With care" means the method works but takes more metal than the knife needs, and on a hard, thin Japanese edge that shortens its life and risks chipping. "Do not" means expect damage.
The whetstone method, in brief
Soak or splash the stone as its maker directs. Set it on a damp cloth or a non-slip base so it cannot travel. Then, for each side:
- Lay the blade on the stone and find the angle the edge was already ground to. Hold it there.
- Push the blade away from you along the stone with the edge leading, working from heel to tip so every part of the edge spends time on the stone. Sharpening is the edge-leading stroke. The edge-trailing stroke has its own job later, when you take the burr off.
- Work one side until a burr forms along the whole length, a faint wire of displaced steel you can feel with a thumb drawn away from the edge, never along it.
- Repeat on the other side until the burr flips over.
- Move to a finer grit, then alternate light strokes to remove the burr entirely.
The burr is the signal that you have reached the apex. Without it you have polished the shoulder of the bevel and the knife will still not cut.
The angle: one number, stated per side
Angles are quoted per side, not as the total included angle, and the two conventions differ by a factor of two. A knife described as 15 degrees is 15 per side and 30 total.
Wüsthof's own FAQ, read 2026-08-24, states that its sharpening angle for standard blades is 14 degrees per side, and 10 degrees per side for its Asian-style blades, the santokus and nakiris. Those are Wüsthof's figures for Wüsthof knives. The page makes no claim about what anyone else grinds to, and neither do we: other makers publish their own numbers and they differ. That is the reason to match the bevel in front of you rather than a number you read somewhere.
You do not need to measure. You need to match what is already there, because grinding a new angle means removing a great deal more metal. If you cannot judge it by eye, an angle guide holds the blade for you.
Pull-through and electric sharpeners
Both work by dragging the edge past fixed abrasive at a fixed angle. On a softer Western knife that is a fair trade: the result is sharp, it takes a minute, and the steel is thick enough to lose a little without complaint.
The problem is that the angle is the machine's, not the knife's. Put a 10 degree Japanese edge through a 20 degree slot and the machine grinds a new, blunter bevel and takes a lot of steel to do it. Hard, thin edges also chip rather than deform. If a pull-through is the tool you will actually use, use it on the Western knife and keep the Japanese one on a stone.
Serrated, ceramic and single-bevel edges
A serrated edge does its cutting on the inside curve of each scallop, so a flat stone cannot reach the working surface. Serrated knives are sharpened with a tapered rod, one scallop at a time, or sent out. In practice a bread knife stays usable for years and this is rarely urgent.
Ceramic is far harder than steel and only diamond abrasive touches it. It also chips instead of bending, so a machine that would merely dull a steel knife can take a piece out of a ceramic one.
A single bevel knife is ground on one face only, with a hollow on the back. Sharpening it means maintaining both that front bevel and the flat back, which is a different technique from a double bevel and worth learning before you start rather than after.
Did it work?
Three checks, in order of usefulness:
The burr. During sharpening, feel for the wire of steel along the far side of the edge. Draw your thumb away from the edge, never along it. If there is no burr, keep going.
Paper. Hold a sheet of printer paper by one corner and slice down through it. A sharp edge takes the paper cleanly without tearing or sliding.
Tomato. Set the blade on the skin and draw it back with no downward pressure. A sharp knife enters on the first pull. This is the test that sent most people looking for this page in the first place.
When to stop and send it out
Chips deeper than the edge itself, a broken tip, a bent blade, or a knife that has been ground badly enough to lose its shape are repair jobs, not sharpening jobs. A professional can regrind an edge in minutes with equipment that would take you hours to match, and doing it yourself at that point usually removes more steel than the damage did.
Safety
Keep the blade moving away from your body. Put the stone on something that cannot slide. Keep your hands dry, because a wet grip on a sharp edge is how most sharpening injuries happen. Never run a finger along an edge to test it. With a honing rod, work with the tip braced and the edge moving away from your holding hand, never toward it.
Frequently asked questions
Can I sharpen a knife on the bottom of a mug?
The unglazed ring on the base of a ceramic mug is abrasive enough to raise a temporary edge, and it is a genuine field expedient. It is coarse, uncontrolled and hard on the blade, so it is worth knowing and not worth making a habit of.
What angle should I sharpen at?
The one your knife already has. Wüsthof publishes 14 degrees per side for its standard blades and 10 degrees for its Asian-style blades; other makers publish their own figures and they are not all the same. Match the existing bevel rather than imposing a number on it.
How often should I sharpen?
Hone often, sharpen rarely. A home cook who hones regularly will usually need to sharpen a few times a year. The honest answer is that the knife tells you: when honing stops restoring the bite, it is time.
Can a serrated knife be sharpened?
Yes, with a tapered rod worked into each scallop individually, or by a professional. Not on a flat stone, and not in a standard pull-through slot.
Is an expensive knife harder to sharpen?
Often, yes. Harder steel holds an edge longer and resists the stone for longer in exchange. That is a reason to learn the stone, not a reason to avoid the knife.
CUSTOMER INPUT NEEDED: This article needs a named author and a one-line credential, per the brief. Nothing has been invented in its place.