Test the sharpness of the knife

Release time:2023-10-12 Number of views: 122

It may seem hard to believe, but keeping the knife as sharp as possible is actually safer than using a dull knife. But after sharpening your knife on a whetstone, how do you make sure it's sharp enough to be safe to use? Below, we list the best and safest tool sharpness tests.


Some people suggest using different body parts to test the knife's sharpness, such as cutting hair from the arm, indentation nails, or even using the tongue. We do not recommend using your body to test the sharpness of the knife. There are many different ways to test the sharpness of a knife that are safer and do not include situations where you could potentially harm yourself.

Different types of tool sharpness test

After sharpening the knife, you can perform four different tests to ensure that you have successfully sharpened the knife. Why test the blade before cutting? It is a good practice to test your blade so that your cut is smooth and clean. Read on to learn how to use our simple tool sharpness test:

1. Paper test

Hold a corner of the paper with your non-dominant hand so that the paper is parallel to you.

With the handle close to your body and the tip facing away from you, place the blade in the middle of the top of the paper.

Slowly pull the knife down the length of the paper until you cut through it.

If your cuts are serrated and uneven, your knife is not sharp.

If your knife keeps cutting down cleanly, then your knife has been sharpened.

2. Tomato test

The knife sharpness test uses tomatoes (or Onions!) As a cut object. The goal is to cut the thinnest, cleanest slice from the tomato without holding the tomato or applying too much pressure with the knife. Try this simple clarity test on a tomato:


Cut off one end of the tomato and place it on a cutting board.

Hold the knife in your dominant hand and hold it perpendicular to the cutting board.

Gently slide the blade from the top of the tomato to the bottom.

If the knife can make clean, straight, thin cuts without requiring too much pressure, then your knife is sharpened enough.

If your knife is having trouble cutting tomatoes, gets stuck during the cutting process or forms jagged cuts, then you need to sharpen your knife.

3. Visual inspection

Look down at the blade and turn the knife left and right to check the edge of the blade for dull marks.

Look for any signs of light reflection. If the top of the blade is bent anywhere, it will reflect light and your knife needs sharpening.

Now, hold the knife to the side so that it is level, check for nicks and notches, and check that the tip is not flattened or falling off.

If you find any defects, your knife needs to be sharpened further.

4. Detect burrs

When you sharpen your knife, the blade bends slightly to create burrs. This is a natural part of the process and why you should always sharpen your knife after sharpening it. A honing knife removes burrs and leaves the blade clean and sharp. Follow these simple steps to detect and remove burrs from a chef's knife:


After sharpening on the whetstone, gently place your finger on the flat side of the blade near the ridge. Slowly slide your finger from the ridge of the knife to the sharp edge of the blade, feeling for any rough edges.

If you feel the blade rough, it indicates that you have produced a burr on that side of the blade, which means that you have made the side the sharpest.

Flip the knife to the other side and start sharpening the edge of that side while detecting burrs on that side.

Remove the burrs, and you're ready to use the knife.

How to keep a sharp edge

After all the hard work of sharpening the knife and testing its sharpness, you'll want to keep your ultra-sharp blade for as long as possible. Follow these tips on how to keep your blade sharp:


Using a honing rod Using a honing rod - a honing rod, also known as a honing steel, does not actually sharpen the knife, but rather straightens the blade. Realigning the blade helps maintain the blade in the long run. Get into the habit of sharpening your knife every time you use it.

Hand wash the knife - In other words, never put the knife in the dishwasher. Using detergent and hot water for too long will dull the blade. Instead, carefully clean the knife by hand.

Dry your knife thoroughly - After hand washing your knife, you need to dry your knife thoroughly with a clean towel. Removing all water droplets will prevent the knife from rusting.

Use a suitable cutting board - Always use a cutting board when making knife cuts. The cutting board should be made of wood, plastic or polyethylene. Never use granite or stainless steel as a base for knife cutting.

Proper knife storage - Designate a dedicated knife storage area in your kitchen. Whether it is a knife drawer, wood block or magnetic block, your knives should be stored properly so that the blades do not become dull.


It may not be the first thought that comes to your mind before you start cooking a recipe, but a sharp knife is essential for making nice knife cuts and working quickly in the kitchen. Make sure you keep your blade sharp by trying one of these tool sharpness tests!