Whether you’re a professional chef or simply a driven amateur, you’ll want to make sure your kitchen knives remain sharp. If you let them get dull, you can bid farewell to precision cuts and say hello to hand strain. Of course, it can be surprisingly hard to tell if your knives need to be sharpened in the first place. Luckily enough, there are several tests you can perform right in your own kitchen, and here are just three.

  1. The Paper Test

This is probably the most popular and widespread way to test the sharpness of a kitchen knife, and there’s a reason for that: it works. It’s also very easy to carry out. Simply take a piece of standard white paper, hold it upright, and then use your other hand to hold the knife and slice downward. If the knife holds a good edge, it should slice your piece of paper clean in two. If it slides off the edge or simply rips the paper, you need to get sharpening.

  1. The Tomato Test

Maybe you want your test to have a more culinary flavour? Fair enough – just go pick a tomato out of your fridge. Next, try cutting that tomato up. Even a dull knife isn’t going to have much trouble getting through a tomato, but what you’re paying attention to is how it gets through. If the knife is sharp, it will slice into the flesh of the tomato cleanly without needing much force on your part. If it needs sharpening, it will catch on the skin, mashing it down before making the cut.

  1. The Onion Test

Don’t have any tomatoes? Not to worry – just grab an onion instead. As well as making us cry, onions are known for having quite slippery skins. A sharp knife will cut straight through the skin of an onion, but one that has become dull will simply slip off. If your knife blade doesn’t cut right in, you need to have it sharpened.