Granton Edge vs Straight Edge

Choose the Granton edge when the blade is long and the food is wet: carving a roast, slicing salmon, cutting starchy vegetables or cheese. Ignore it on a short knife, and never pay a premium for it. The scallops sit above the cutting edge, so they cannot make a knife sharper or thinner where it matters — they break the suction that makes a slice cling to the steel, and the only source we could find that actually tested them concluded they were unnecessary on santokus and useful on slicers.

This comes up because the same knife is often sold two ways at the same price, and the listing copy never explains the difference beyond “prevents food from sticking.” Three names, one feature: Granton edge (English, from the patent), Kullenschliff or hollow edge (German), and dimpled or fluted on some Japanese and professional lines. All describe oval scallops ground into both faces of the blade just above the edge.

Where the feature comes from

It is not a modern marketing invention. America’s Test Kitchen records that the hollows were “patented in 1928 by what’s now the Granton Knives Co. in Sheffield, England,” which is why the English-language name is a company name. The design spread first through butchery and slicing knives — long blades working on wet protein — and only later onto santokus and chef’s knives, where it is now mostly a styling choice.

What the scallops do — two mechanisms, not one

1. They break suction. A flat, wet slice pressed against a flat steel face is held there by surface tension and the absence of air. Scallops create pockets, air gets in, and the slice falls away instead of riding up the blade. This is the claim every listing makes, and it is real but conditional: it needs a wet or starchy surface and a reasonable area of contact to matter at all.

2. They remove metal.This is the part the marketing leaves out and the part a testing source puts first. America’s Test Kitchen notes that “many sources claim the design prevents food from clinging to the blade,” then adds a second purpose in its own words: “the scallops make the blade thinner and lighter to help it slide through food” while “maintaining some rigidity at the spine for control.” In other words part of what you feel from a hollow-edge knife is simply less steel in the way.

Both mechanisms are about the blade’s faces. Neither touches the apex. That is why a hollow edge cannot substitute for a thin grind or a keen angle, and why thickness behind the edge remains the property to buy first.

What they do not do

• They do not make the knife sharper. Sharpness is the apex and the geometry immediately behind it. Two knives with the same steel, hardness and edge angle arrive equally keen.
• They do not change the steel or the hardness. A hollow-edge Wüsthof santoku is the same forged X50CrMoV15 at the same published 58 Rockwell as the rest of the forged Classic line; the scallops are a grinding operation, not a metallurgical one.
• They do not fix wedging. If a blade splits a carrot instead of slicing it, the cross-section above the edge is too fat, and scallops higher up the face will not change that.
• They do not stop everything sticking. Starchy potato will still cling to parts of the blade; herbs will still bruise and gather. A hollow edge reduces a problem rather than removing it.

Where it pays off, blade by blade

The Japanese version of the same idea

Japanese makers address blade-to-food contact differently. Instead of a row of machined ovals, many clad knives carry a tsuchimehammered finish — dozens of small dimples beaten into the cladding, which break contact the same way. The Yoshihiro 240 mm slicer we track is a good example: a VG10 core under hammered Damascus, where the dimpled face is doing functional work on exactly the kind of long wet cut the Granton edge was patented for.

The practical difference is what else you are buying. A Granton grind is usually offered on an otherwise identical knife at the same price, so the decision is free. A hammered finish usually arrives on a clad Damascus blade, so you are paying for cladding and appearance as well as release — which our Damascus explainer gets into. Note also that the general reference on Japanese kitchen knives frames the tradition around grind and bevel geometry, not surface treatment: the cutting argument in Japan is about how thin the blade is, which is the same point this page keeps returning to.

Sharpening a hollow-edge knife

Exactly as you would sharpen the plain version. The bevel you work sits below the scallops, so the angle, the grit progression and the burr removal are unchanged — the method in how to sharpen a knife applies without modification, and the general sharpening reference’s coarse-to-fine logic is the same.

There is one geometric consequence worth knowing, even though most home cooks will never meet it: a knife sharpened back far enough, over many years, will eventually have its edge reach the scallop row, at which point the edge itself becomes scalloped and the blade is finished. It is a long way off — and it is a reason to sharpen conservatively rather than aggressively, which is also the advice in how often to sharpen a knife. Care is likewise unchanged: hand wash, dry immediately and store so nothing touches the edge, per the maker guidance collected in knife care.

So which should you buy?

Take the hollow edgeif the two versions cost the same and the knife is a slicer, a carving knife, or a chef’s knife you will use on potatoes, cucumbers, cheese and cooked meat. It is a small, free improvement in a narrow set of jobs.

Take the plain bladeif it is cheaper, if the knife is short, or if you simply prefer the look. On a 165 mm santoku you are not giving anything measurable up — and the testing source that looked hardest at this feature put its own santoku award on a knife without one.

Spend the money elsewhere if there is a price difference. A keener published edge angle, a harder core steel, or a thinner grind all change more cuts per day than surface release does. Our gyuto roundup and Miyabi page are where those numbers are, and best knives for cutting vegetables covers the sticking problem from the other direction — shape rather than surface.

We own none of these knives and have run no cutting tests of our own; the testing claims above are attributed to America’s Test Kitchen, and the specifications are the makers’. Our methodology page explains the approach, and prices come only from our live price layer with the date they were read.