Single bevel and double bevel knives explained

The difference between single-bevel and double-bevel knives is fundamental.

A double-bevel knife has cutting geometry on both sides of the blade. A single-bevel knife has the primary cutting geometry on one side.

That difference changes how the knife should be sharpened.

Double-Bevel Knives

Most familiar Western-style kitchen knives ( and many Japanese too ) are double bevel.

The cutting edge is formed by two angled surfaces meeting at the apex.

The angles on either side can be adjusted according to the knife's steel, construction and intended use.

Single-Bevel Knives

Some Japanese knives such as certain yanagiba, deba and usuba designs ( below ) can use single-bevel geometry.

The flat side and bevelled side have different jobs.

They are not simply a normal chef knife with half the sharpening removed.

Why It Matters

If you sharpen a single-bevel knife as though it were double bevel, you can change the knife's intended geometry and it will pull to one side.That is why specialised knives need specialised knowledge.

Global Knives As An Example

We regularly receive Global knives, including single-bevel models.

Our published Global guidance explains that single-bevel Globals are sharpened on one side only, in accordance with their intended design.

The important point is that the knife's geometry dictates the method.

Not Every Japanese Knife Is Single Bevel

This is another common misconception.

Many Japanese chef knives, including santoku and gyuto-style knives, are double bevel.

'Japanese knife' does not automatically mean 'single bevel'.

What should you do?

If you own an unusual or expensive knife and are unsure of its geometry, identify the exact model before sharpening it. Look at the manufacturer's specifications and if in doubt email us before sending it in.

However, we assess all knives prior to servicing so we identify exactly how the bevels align prior to sharpening.