What Are The Different Ways to Sharpen Knives?

In the following article, you can read about the tools and methods, the advantages and disadvantages, and technical questions for buying the correct sharpener for your knife.


Grits – What Is It And Why Its Important In Knife Sharpening?

Grit refers to the coarseness of the diamond, a water stone sharpener – the abrasive material on the sharpening tool. Lowest the number, the bigger the grits.

1000 Grit and Under – Coarse Stones

A sharpener tool under 1000 grit is used to fix a damaged, chipped blades or very dull knife that barely have a cutting edge. Use these only occasionally because, over time, they can wear down the blade.

Grit between 1000-3000 – Medium Stones

Between 1000 and 3000 grit stones are great to sharpen a dull knife that are not damaged. Preferably, choose less coarse stones, between 2000 and 3000 grit, for more frequent, but not daily or weekly sharpening.

4000-8000 Grit – Finishing Stones

To maintain the edges of knives, use the finest stones between 4000 and 8000 grit. Using this results in highly refined edges and can be used more often. Usually, a sharpener with 5000 grit is perfect for the purpose; there is no need to go further.

Knife Sharpening Tools

There are different ways to sharpen knives, and several tools are available that are relatively easy to use and result in razor-sharp edges.

To properly sharpen your knife, it is useful to practice on an old, not too expensive blade, like a chef’s knife. Choosing the right knife sharpener is also important – it has to be adequate for the type of blade but also for you.

Diamond Based Stone

Using diamond-based stones is the most expensive method regarding their initial costs, but they last for a long time. For those using them frequently, even daily, they will last for a few years, with proper maintenance. With infrequent use, they can last for up to 10-20 years.

These stones are not actual stones but metal plates with small industrial pieces of diamonds. Diamond is one of the hardest materials on Earth, so not surprisingly, diamond stones are the toughest sharpening tools. Sharpening with these makes the process very fast and retains their flat shape, not requiring re-flattening. Additionally, they are helpful in flattening Japanese water stones.

How to Use Diamond Based Stones?

To sharpen your knives, wet the stone with water, but avoid oil as a lubricant. You can use dry as well, but wet stones are desirable. As you sharpen, apply more water, if needed.

During the process, hold the knife-edge on the stone at an angle of around 15-20 degrees, depending on your knife.

Make gentle strokes, keeping your hand far enough to avoid injuries, and don’t go too fast because it can over sharp the blade edge.

From time to time, try the knife to test it and stop when the desired sharpness is obtained.

Japanese Water Stone

One of the easiest ways to sharpen stainless steel knives is using Japanese Water Stones. They are useful for sharpening and polishing as well and are less expensive than diamond-based stones. However, they can get hollow after multiple usages and have to be flattened because they are much softer and porous.

Traditional water stones consist of a clay-like material embedded with fine silicate grains. However, synthetic versions are also available because conventional material is scarce in nature. These synthetic versions consist of silicon carbide or aluminum oxide.

How to Use Japanese Water Stone Sharpeners?

Their name refers to their usage – prior to sharpening, they need to be soaked in water for a few minutes (5-10 minutes) but don’t leave them in it for much longer.

Once wat and stopped bubbling (all air pockets are filled with water), hold the knife-edge to the stone at the angle of 10-15 degrees (for Japanese-style blade) or 20-30 (for Western-style blade).

Put your index finger on the knife but not too close to the blade edge. Move the knife back and forth from the tip all the way to the end of the blade. Use a water spray to wet the stone if the lubrication is not adequate.

Repeat the movement around 7-8 times – it will be enough to sharpen a stainless-steel knife properly.


The most affordable way to sharpen your knives is using sandpaper. Please note that this is a DIY method – buying a sharpening tool is preferable. However, people who only have a couple of knives that do not require sharpening very often and don’t want to buy a sharpener use sandpaper.

Additionally, beginners can benefit from using sandpaper. Water stones and diamond stones are very hard and sharpen the knife fast. Sandpaper is softer and needs more work to sharpen the knife.

However, this can be an advantage – if you are sharpening your knife and don’t hold it at an appropriate angle, the cutting edge won’t be consistently sharpened. With the sandpaper method, you can correct the angle without ruining the edge.

How to Use Sandpaper for Sharpening?

To put together your own simple sharpener, you will need sandpaper and a flat mousepad or thicker leather surface. Make sure the surface is completely flat; there should be no bumps and unevenness.

Use sandpaper with a sticky bottom so that it will stay on the mousepad. You can also use tuck tape to stabilize it. Use micro-abrasive film, from 15µm down to 0.3µm.

Alternatively, wrap the sandpaper around an object with a flat surface, for example, brick.

Sharpen the knife with a back-and-forth motion on the sandpaper. Don’t apply too much pressure on the sandpaper; just lightly push and pull it. Make sure that both sides are equally sharpened.

Pull-Through Manual Knife Sharpeners

There are a variety of manual sharpeners available that are easy to use and generally inexpensive to buy.

Although the three other types are also manual methods, the pull-through sharpeners are specifically designed for different types of knives, and you don’t have to worry about holding the knife in the right position. It guides the blades for you, making it very easy to use, even for amateurs.

Hence, when choosing one, make sure that it is suitable for the specific knife you want to sharpen. For example, take into consideration the angle of the edges – some sharpeners are good for Wester types of knives but not for Japanese style.

Electric Sharpeners

Electric sharpeners are fast and seem very easy to use. Most professionals, however, discourage using them because of two main reasons. First, they remove a large amount of material during each sharpening. After 10-12 sessions, 0.5 cm (around 0.1 inch) of the blade is lost.

Second, using them does not result in adequate edge, even the most expensive ones. Cheaper knives that you do not mind replacing every few years and only use at home are okay to be sharpened with electric sharpeners.

But if you prefer to retain your expensive, high-quality knives, choose a manual method.

Sharpening Steel or Honing Steel

Honing steel (also called sharpening stick or steel) is a rod-like, flat, round, or oval-shaped sharpening tool. It can be coated with steel, diamond, or ceramic.

Although honing or sharpening steel are often used interchangeably, these are two different tools. Let’s look at their function and how to use them!

Sharpening Steel

As the name indicates, this tool is made for sharpening the knife. The coating is ceramic or diamond so that they are harder than the honing steel. This tool is suitable for sharpening knives that have not been sharpened for a long time and are very dull. If used properly, you can restore the V shape of the edge.

How to Use a Sharpening Steel?

When using this tool, hold the knife at the right angle – generally, 20 degrees, but it depends on the type of the knife.

Place the heel of the knife to the bottom of the sharpening steel, and move it up. When reaching the top of the rod, the point of the blade should touch it.

Make sure that only the blade edge is touching the tool. Repeat the process 2-4 times on each side.

Be careful; only move the knife while holding the rod steadily because it is easier to control the process!

Honing Steel

The honing steel is used to re-align the knife’s edge – keep it straight in the proper position and correct any curves. It does not remove any material from the blade, so it does not sharpen it.

However, if the blade is straight, the knife is easier to use, so it might feel that the edge is sharper.

Some professionals hone their kitchen knives before every use, but it is not necessary for home cooking.

How to Use a Honing Steel?

Lay the knife against the honing steel at a 20-degree angle (most Western-type knives). If the angle is too big, the honing will not be sufficient and might leave scratches on the blade.

If too small, it can hurt the edge. Move the knife up and down along the rod, starting at the heel and finishing at the tip, as the image shows.

Sharpening Different Types of Knives

Sharpen Stainless Steel Knives

Diamond-based stones, using very light pressure, results in very sharp edges in 5-10 minutes. If you only have water stone, it will probably work well but make sure it has a flat surface.

Pull-through manual systems are great too, and some offer diamond abrasives. Sandpaper is a budget-friendly option.

Buy silicon carbide sandpaper between 60 to 1200 grit. Aluminum oxide-based versions are not necessarily tough enough to grid the hardest stainless-steel blades.

It takes around 5-10 minutes to sharpen a stainless-steel knife with sandpaper.

Sharpen Carbon Steel Knives

You can use any method mentioned above. The best ways are probably diamond stone and water stone.

If you use your carbon blade excessively, sharpen it once a month to keep a nice, sharp edge. To maintain sharpness, be sure to also clean carbon steel knives regularly.

Sharpen Ceramic Knives

Ceramic blades are the best in edge retention and do not require frequent sharpening. But it is possible if you need to. However, they are especially brittle and very easy to break. Hence, you must not exert too much pressure on a ceramic knife.

Sharpen it very lightly, preferably with both hands (see image below). Use your fingers to apply force on the blade, not your whole arm: it is easier to control the knife this way. You can do up and down or just down motions.

Due to their toughness, diamond-based stones are the best to sharpen ceramic knives. Regarding the grit, start with 200 to fix large chips, if necessary, and gradually work your way up to 1500.

Water stones will do the job as well but are definitely harder to use and takes longer. The sandpaper method on ceramic knives is not impossible but takes a while to obtain the desired sharpness.

Hire a Professional to Sharpen Knives

Probably the best and most reliable way to sharpen your knives is simply sending them for professional sharpening. You will get a perfectly sharp, not damaged knife.

Professionals know what type of sharpener to use to get the best results and take into consideration the type of blade they are working on. They will tell you how often should you sharpen knife to keep its cutting edge.

Professional sharpening is quite expensive – if your blades need regular sharpening, learning how to do it properly will save you a lot of money.

How To Check If The Knife Is Sharp Enough?

There are different testing techniques to check knives sharpness and cutting edge. Following are the most common methods to check if your knife is sharp enough.

Paper Method

Upon sharpening, an excellent way to check if the blade is done is to hold your knife in the air and try to cut a piece of paper downward, holding it between your fingers.

If it is easy, and the cut is nice and even, it is a sign that the knife is well-sharpened. When cutting, don’t exert too much force – let the weight of the knife do the job. If the blade rips the paper, it needs further sharpening.

Hair Method

Alternatively, try to cut the hair on your leg or arm without touching the skin (so don’t use the knife as a razor). A sharp blade can cut the tiny hairs, while if they fold under it, the blade is still dull.

Be very careful when using this method! Don’t cut yourself with a razor-sharp blade!

Similarly, you can use your hair by trying to find some that come easily off your head.

Hold the knife, edge facing up, and try to cut the hair strand. A sharp edge will cut right through it, just lightly touching it!

Tomato Method

The tomato method is terrific for any type of knife but is most often used to test kitchen knives.

The tough skin but soft inside of the fruit makes tomato an excellent testing tool. Just place the edge on the fruit and exert some pressure.

If the blade slides through the tomato, good job! A smashed fruit indicates that the knife is dull and needs more work.

Final Thoughts

Sharpening your knife with the correct manual method will ensure easy usage and long life. Before sharpening, make sure you know what type of blade you have, the right angle of the edge, and which method is the most suitable for it.

Use a knife sharpener with care and check the edges carefully, without cutting yourself. Although knife sharpening is not difficult after some practice, if you are unsure, don’t hesitate to choose and book a professional knife sharpening in nyc.