How to Sharpen a Tanto Knife

There are many different styles of tantos out there, but they all share one thing in common- they have an angled transition from the front to the back of the blade, typically eliminating the belly in favor of two straight sharpening edges. The marketed purpose of a tanto-style knife is a durable piercing edge.

Inspired by Japanese short-blades, modern tactical versions of tanto knives tend to feature more extreme transitions and vary in spine thickness, from acute thickness for more puncturing power at the tip to thinner, EDC-style spines for a more traditional pocket carry.

The first step to success when sharpening a tanto is to treat the two edges as two separate knives. That means ensuring you understand the angle of each edge (which may or may not be the same) and you are treating the transition point between the two edges as if it were the tip of the knife.

The biggest challenge to sharpening a tanto blade is maintaining the transition point between the edges (the thing that defines the blade style). If you are not careful, it is easy to slowly erode the transition over time (we’ve seen more than a few tantos at each tradeshow that were essentially quirky drop points by the time they got to us).

You can restore the transition point if you’ve rounded it out, but it will require some time (and some material take-off) to happen, especially with super-steels. Watch the video above to learn more on restoration techniques.

Some tanto-style knives, like the Benchmade Vector, present additional sharpening challenges by having a recurve in the primary belly AND an intentional angle change (14 degrees in the belly) in the nose edge (18 degrees). This is a perfect example of why treating each edge as its own beast is so important.

Follow standard sharpening practices for each edge and you’ll have a sharp, dual edge knife with extra piercing power for decades to come.