Informational Guide

Boning Knife Vs. Fillet Knife

Slicing up your catch can be challenging. Learn about the differences between boning vs fillet knives & see which is best for you.

by Andrew

Informational Guide

Boning Knife Vs. Fillet Knife

Slicing up your catch can be challenging. Learn about the differences between boning vs fillet knives & see which is best for you.

by Andrew

by Andrew

Congratulations, you have managed to catch some delicious fish! Filleting those fish comes to mind, but it may not be all that easy. Walk into any kitchen, and you will see there are knives that come in all shapes and sizes. Which one is best for your application? This article will discuss the range of options for knife selection and the importance of choosing the right tool. By the end, you should have a better understanding of how to choose and when to use a boning knife vs fillet knife.

A boning knife is a medium length knife with a thin but sturdy blade. These have a blade length between five inches and seven inches which is straight and sharp. These are great for separating meat from bone, not only on fish but on any meat or poultry. A boning knife needs a tough blade because it sometimes gets used to not only cut but pry bones from meat. The boning knife is usually used to supplement a fillet knife in most scenarios but can be used as a makeshift fillet knife in special situations when fillet knives are not available.

boning knife

What Is A Fillet Knife?

A fillet knife is exactly what you think of when you picture someone cleaning fish. Traditional fillet knives are between five and nine inches long. They have a distinct upward curve that makes them ergonomically comfortable when removing the fillets from fish. In conjunction with the slender, flexible nature of the blade, this shape makes it great for separating the meat of the fish from skin and scales. These are purpose-built for cleaning fish.

Boning Vs. Fillet Knife: Key Differences Explained

  • Structure & Design
    Boning knives are "full tang," which means that the blade material runs through the handle down to the base. This gives the knife extra rigidity for tackling hard joints, ligaments, or tendons that you may need to separate from the meat. The blade has a distinct sharp point where the cutting edge and the backbone of the blade make subtle curves toward one another. This feature gives a user the ability to poke and pry when using the boning knife. Alternatively, you will not usually find a full tang version of a fillet knife. A fillet knife blade itself has a very distinct shape that is specialized for fish cleaning. The blade is wide at the base but becomes thin very quickly down to the sharply pointed tip. This allows the user to be precise when working in the thin margins between skin and meat. The swooped back blade shape also allows the user to work from many angles while cutting.
  • Material
    Both blades are made from high steel, and more commonly, stainless steel. This prevents the blades from corroding or decaying over time. Higher quality knives will be made of higher quality raw materials. Buying a quality boning knife and fillet knife is not only about the longevity of the blade but the ability to sharpen the blade over and over. Keeping a sharp edge on a blade has a significant impact on the cleanliness and ease of cuts, so while a less expensive knife may appear as nice as the more expensive version, it may only stay sharp or able to be sharpened for a shorter lifespan.
  • Handles
    Boning knives are traditionally used in the finishing stages of preparation. This is a case where the blade functionality is more important than handle material selection. On the other hand, fillet knife handle material selection is super important. Fillet knife handles or grips have traditionally been made from wood that has been treated to resist decay, but you could choose a steel handle, one made of plastic or polypropylene. When choosing a fillet knife, you should be looking for a non-slip, antimicrobial handle that will be easier to grip in any condition. The high-density polypropylene handles are perfect for this.
  • Intended Use/Purpose
    Fillet knives are meant for fish cleaning, so are specialized in their purpose. The boning knife, on the other hand, could be used in desperation as a makeshift fillet knife. You would not want to use this tool for this job all of the time for efficiency, but it could work. Think of this as using an adjustable wrench when you could be using a ratchet with the correct socket; both will work, one will work way more efficiently. The boning knife is specialized for, as the name states, boning out meat. This is not specific to fish as the fillet knife is; therefore, it can be used more often in other circumstances.
  • Blade Thickness
    Blade thickness is important when we are discussing boning vs. fillet knives. The boning knife will be thicker and heavier duty than the fillet knife because it is not intended to work between meat and skin, but rather meat and bone or connective tissue. Fillet knives are lean and slender, enabling them to be flexed as they work through the fish. This allows the user to carve the meat from bones effectively and then skim the skin off the fillet with ease.
  • Blade Flexibility
    Fillet knives are known for their flex. Flexibility is key when filleting any size fish. You do want to have some resistance to the flexibility so that you are not in danger of snapping the knife off, but more likely than not, the more flexible, the better. Boning knives are the opposite. You need a strong and sturdy blate to tackle the dense bones of larger game. Rigidity is a crucial factor when choosing a boning knife and is also the main factor that makes boning knives the wrong tool for filleting.
  • Maneuverability
    Buying the right fillet knife for your application is an important factor to consider. You will want to buy a knife that fits your hand nicely so that you are not uncomfortable when filleting or boning. You also have to consider that a fillet knife is generally used parallel to a cutting surface while the fish is lying on its side. You will want to find a knife that fits your fingers between the grip handle and the cutting surface. Boning knives are used upright, so this is not as much of a factor in a boning scenario.
  • Size
    Choose blade size based on the fish you plan to catch when shopping for a fillet knife. You want a blade that is longer than the fish is from the dorsal fin to the pelvic fin. Ideal length will give you about an inch of blade at the tip and the same at the base mid fillet. With a boning knife, the same applies as far as size choice. You want a knife substantial enough for the job but not too large that it impedes efficiency or maneuverability.

People Also Ask (FAQs)

Can you use a boning knife to fillet a fish?

You can use a boning knife to fillet a fish in certain scenarios, but it is not ideal. The knife is too stiff to contort and twist around the spine and ribcage of a fish. You will end up collecting too many unwanted bones in the fillet, or you will end up accidentally cutting through the fish's spine and damaging both fillets on the fish.

Do I need a fillet knife?

You do need a fillet knife. If you plan to keep your catch and prepare it for a meal, you will absolutely need this tool. If you do not have a fillet knife, you will have more anxiety when it comes to cleaning your catch, you will have to work harder, and it will take longer for you to perform the simple task of filleting. This will ultimately lead to eating less of your catch, and worse, could kill the desire to go fishing!

Should a boning knife be flexible?

No, a boning knife should have a sturdy, rigid blade. When cutting through tendons or joints, you will appreciate having a knife with a solid backbone. A flexible knife would be dangerous in this scenario and could break or deflect off the meat in an unpredictable manner.

Is a boning knife necessary?

Yes, boning knives are an important piece in cleaning or preparing not only fish but any meat. Removing bones is always part of any fish cleaning and almost any butchering.

What are the best fillet & boning knife brands to buy?

The best brands to buy can be found in the "10 Best Fillet knives" section on our website! In our opinion, you can not go wrong with the KastKing, the Morakniv, or the Rada Cutlery knives. Something we did not touch on in this article is electric fillet knives, which are amazing when cleaning large or large amounts of fish. Check out the Rapala brand electric fillet knife.


At the end of the day, when asking yourself, "is a boning knife the same as a fillet knife?" Remind yourself what we have discussed here in this article. A boning knife is not a fillet knife, and the same goes for a fillet knife being a boning knife. They each have their respective pros and cons. The flexibility and slenderness of the fillet knife seamlessly removes meat from spines, skin, and scales. The backbone of the boning knife is tough enough to separate meat from tendon and bone. To be prepared for your next fishing trip, we suggest having both at your disposal.