How Long Should A Kitchen Knife Stay Sharp? (Best Answer)

Many people know the difficulty of using a blunt knife. So, they tend to sharpen it whenever the edges are too blunt and don’t cut through properly. But how long do the knives stay sharp?

Excessive sharpening will make the edges too thin, and it will eventually chip away. So, it is important to know how long a knife can stay sharp and when it should be sharpened again. 

Let us find out the longevity of the sharpness of a kitchen knife and how often you might have to sharpen it.

How Long Should a Kitchen Knife Stay Sharp?

An average kitchen knife with stainless steel blade can stay sharp for at least six months after a single sharpening session. You must also consider the facts that you have to maintain the knives properly and make sure the edges are intact. Even with heavy usage, you can expect the knife to last six months with occasional honing. You might have to replace a kitchen knife only when the knife edge becomes completely dull and lacks material that allows the sharpening. 

To understand how long the sharpness can last, you should know what sharpness means in a kitchen knife. Let us discuss the technical details of sharpness in a knife and the reasons for a knife getting blunt. 

Sharpness in Knives

A knife is manufactured by the process of casting and forging. After forging the knife, you can find that it looks like a thick rectangular block. There are no sharp edges in this stage of knife manufacturing. 

The blade is repeatedly hammered to make it thin, and it is sent to a process called sharpening and surface finishing. Here is where the knife edge is made.

In the process of sharpening, the thickness of the blade is further reduced by removing the steel at a particular angle. So, the edge becomes thinner and thinner to a point where it begins to become sharp.

If you look closely at the blade edge, you can find the aberrations on the edge that indicates the removal of the material. Therefore, whenever you sharpen a blade, you are removing material from the edge.

If you keep on removing the metal from the edge, it will become like a wedge and no longer be able to cut any material. 

The sharpness of the knife can be measured using the Brubacher Edge Sharpness Scale (BESS). It provides a value of sharpness in terms of pressure required for cutting. If the sharpness is higher, the pressure required to cut is lower. So, the lower the BESS value, the higher will be the sharpness of the blade or knife.

How a Sharp Knife gets Blunt?

A sharp knife is made blunt due to the constant removal of metal in an uneven manner. The metal edge is worn off due to friction when rubbed against other objects. So, this removal of metal due to friction causes the blade to get blunt.

The friction caused can be higher when the steel knife blade is rubbed against another metal or against an abrasive. But in the case of a kitchen knife, the chances of the blade rubbing against a hard surface is rare. 

Most of the time, a kitchen knife is used for cutting veggies, meat, etc. Very rarely it encounters a hard surface. Maybe when cutting meat or a fish, it can encounter a bone which is an abrasive material. Only when the knife is rubbed against such hard materials, the material is removed unevenly.

So, the kitchen knife takes a long time to become blunt. If you properly sharpen it and maintain it by occasional honing, you can have long-time sharpness. That is why you will not find the need to sharpen a normal kitchen knife when you buy a new one.

Therefore, a sharp kitchen knife will last a very long time with proper maintenance. Now let us discuss the ways to maintain a kitchen knife so that you can preserve the sharpness for a long time.

How to Maintain Kitchen Knife Sharpness?

To maintain the sharpness of a kitchen knife, you have to do the following things:

• Always store your kitchen knife in a sheath or in a knife block. It will prevent accidental damage to the knife and maintains its sharpness for a very long time.
• Try to sharpen the knife properly at least once. If you didn’t sharpen it properly, you cannot expect it to remain sharp.
• Know the proper methods to cut and the method to use a cutting board. This will help you to avoid chipping the knife edge.
• Don’t rub the knives against abrasive surfaces unless it is a sharpening stone.
• Never leave the knives out on the kitchen table since they may be prone to damage.
• Use appropriate knives for the required task. Don’t use a chef’s knife for boning or a butter knife as a meat cleaver.
• Try to hone the knife once a week or before cutting a hard material. This will ensure less damage to the knife edge.
• If you properly maintain the knives in this manner, you can easily maintain the sharpness in the knives for a long time. 

How Often Should You Replace Kitchen Knives?

There isn’t a defined timeline to replace kitchen knives and they can last more than a year or two easily even with heavy usage. Most users don’t face an issue with the knives even after using them for more than two years. But there can be some issues with the knife handle or the sharpness of the blade after such long years of usage.

The major materials used in the production of kitchen knives are Carbon Steel and Stainless Steel. These both alloys are highly resistant to abrasion and erosion. So, when it comes to kitchen use, it will not erode easily and never rust even with continuous usage with water or humidity.

That is why it is necessary to buy knives from a reputed brand or by checking the quality. If the knives are manufactured poorly, you can find them to rust, bend, and even break into two easily.

Therefore, if you choose to buy kitchen knives made of carbon steel or stainless steel from a good brand, they will last more than you expect. Even if you sharpen it several times the blade will not degrade easily.

There are some instances where you have to compulsorily change the knife. If you get to know these reasons, you can take care of your knives more intimately and avoid spending money to buy a new one.

When You Should Replace the Kitchen Knives?

We already established the longevity of knives. Now we shall find out the possible scenarios where the knives may get damaged and when it is absolutely necessary to replace them.

Blade Damage

Using the blade against ceramics, glass, granite countertops, or even against carbon steel and stainless-steel surfaces can chip the blade considerably. If you find the blade in such a condition, replace it immediately.

So, you must avoid using the blade over such surfaces. Always use a wooden cutting board while using the knife for cutting meat or veggies.

Loose Handle

The handles are fixed to the blade with the help of rivets. When this riveting is done poorly or when it becomes loose, the handle may start to detach from the knife. It will be very uncomfortable if the handle is shaking when you are using it. So, it becomes necessary to change the knife.

The reason for this to happen is not entirely the user’s fault. It may be a manufacturing defect. But if you are using the knife under heat, there are chances where the rivets undergo constant heating and cooling that result in shrinking of the rivet.

Broken or Bent Tip

The tip is very important to perform some delicate cutting and to perform some fine work while cooking.

Therefore, if you find the tip to be broken, you have to replace it. Even if you don’t have the culinary skills to work with a pointed knife, it is best to replace it.

You can avoid such incidents by keeping the knife inside a knife sheath or wooden storage blocks. Be careful while handling the knife and try to store them properly after every usage. Don’t leave them on the countertop after using them.

Eroded Blade

Every time a knife is sharpened, some amount of the metal is removed which makes the edges sharp. So, over the years, the knife will become very thin and at one stage, there will not be enough width to sharpen it.

During such instances, you will have no choice other than to replace the blade right away. Mostly, we will not use the knives till that point. But if you are too attached to one, you may have to look into it and replace it.

Also, there can be rusting after long years of usage. The blade will start to erode right from the time it is put to use. Therefore, it is safe to say that it is best to replace your knives only when you come across these issues. Otherwise, every good quality knife is good to go as long as you maintain it properly and prevent these situations.

Conclusion

Kitchen knives can usually stay sharp for a long time. It is not a condition to sharpen it often and you don’t have to regularly hone it too. But make sure to follow the maintenance procedure for the knives so that you can have a long life with them.