The flexible belt helps accommodate knives of all different sizes, though we found that it also leaves a lot of wiggle room for the blade, making it somewhat difficult to keep knives at the exact correct angle through the entire sharpening process. The Easy Edge theoretically can sharpen a serrated knife, but it only sharpens the flat edge and not the serrations themselves, so we recommend against it. This knife sharpener is simple to use and sharpens very well, but with its high price, it's probably best for someone who spends a lot of time in the kitchen or is a professional chef. We calculate the difference between the dulled and sharpened knife to see how effective the knife sharpener has been. Effectiveness: The Edge-on-Up tool helped give us an idea of each sharpener's efficiency, but we also tested our knives immediately before and after sharpening to gauge any noticeable differences. We hand sharpen all Global Knives using our specially designed water-cooled diamond whetstones which means we can get the knives sharper then new. When new even Global Knives are machine sharpened, and our hand sharpening produces a much sharper edge. We rate each knife sharpener on how easy it is to set up and use, plus how easy the instructions are to follow. Things we learnt testing knife sharpeners

Pull the knife blade along the sharpening steel towards you, with enough gentle force that you can hear a grinding noise. Work Sharp Electric Culinary E2 Kitchen Knife Sharpener: This sharpener is easy to use and has an excellent price for an electric model, but you get what you pay for. We found that it did just an OK job at sharpening, while its feet let it slide around on the countertop, which is a definite safety hazard. The electric Chef'sChoice 130 Professional Sharpening Station is simple to use and works well on many different sizes of blades, while the manual Longzon 4-in-1 offers similar quality with a low price tag. For those on a budget, the electric Presto EverSharp is excellent, too. How We Tested A honing steel, sometimes also called a honing rod or a sharpening steel, doesn't exactly sharpen your knife. Instead, it realigns the cutting edge to smooth out microscopic bumps and jagged edges.Carrie Honaker, who updated this roundup, is a food writer who has wielded many knives over the years. As a restaurateur and avid home cook, she knows the importance of caring for your knives to maintain steady, sharp edges. Her work has appeared in many publications, including Bon Appetit, Allrecipes, and Wine Enthusiast. Sharpening a knife blade removes tiny bits of metal, and those will need to be removed from the sharpener once in a while. Many models have a compartment in the bottom to collect metal filings, which you can simply dump into the trash and wipe clean with a wet cloth. (If there's no compartment, turn the unit over and lightly tap to get the filings out.) You can also clean the abrasive parts with a cloth or a soft brush dampened with water; make sure to let everything dry completely before using again. Unless the directions say otherwise, it's not a good idea to use soap or any kind of oil to clean a knife sharpener, as you can damage the abrasive. A honing steel is a long rod, often included in knife sets, along which you run both sides of the blade before you start slicing and dicing. It helps maintain the integrity of the blade, straightening out some of the microscopically uneven spots on the edge without actually removing any metal. Used regularly—as in every few times you use the knife—it can help stave off dullness, but you'll still need to sharpen your knife on occasion.

How well the sharpened knives performed: We examined their ability to slice through paper, tomatoes, and carrots both before and after sharpening. For models that claim to accommodate serrated knives, we tested their slicing performance using a baguette. A whetstone is much harder to use. To get a good result, you need skill and practice, plus considerable patience. Each knife sharpener will have its own specific directions, and you should always follow those, but in general, you insert the blade into the slot and pull it through with even pressure several times. It's important to make sure the full blade passes over the abrasive, all the way from heel to tip. Then, you repeat the process on the other side of the blade (though some sharpeners work on both sides at once), first using the coarsest slot and then each of the finer ones. To discover the best knife sharpeners on the market, we collected an array of dull knives—plus several boxes of Band-Aids—and tested their performance slicing through paper, carrots, and tomatoes (and a baguette, for serrated blades), both before and after sharpening. We also measured each knife's sharpness scientifically, using an Edge-on-Up tool to record the exact amount of force needed to cut through a standard material. Jason Horn, a commerce writer for The Spruce Eats, updated this roundup to include data from our extensive tests of 22 sharpeners—10 electric and 12 manual—by both freelance testers and in our Lab in Birmingham, Alabama.

Finish with a honing steel for best results. Rinse and dry the knife. You may also need to clean up the area around the whetstone. When the sharpener has more than one setting, the coarse setting is the sharpener and the fine one is normally similar to a honing steel. We then sharpen the knife with its dedicated knife sharpener according to the manufacturers' instructions. If your knife sharpener has a fine or honing setting, run it through that once or twice after the coarse setting. Do this in the same way, but with less force. To keep your knife sharp, use the fine setting once after every couple of hours' use.