Safety
Electric knives should have clear and easy-to-understand safety directions. Blades should be easy to insert and have enough width so you can handle them safely. The knife should have a safety lock button to keep you from running the knife accidentally.
Function
Electric knives are not all for the same purpose. If you want an electric carving knife for meats, look at those with longer blades. For an electric knife to cut fresh breads, look for a model with a shorter blade. Some electric models come with both sets of blades.
Types
You'll see cordless models and those with cords. Typically, the electric knives with cords have more power. The cord should be long enough to not be in the way as you use the knife but long enough to reach an electrical receptacle near your cutting surface and still give you plenty of room to cut. Cordless models should have batteries with long enough operating time to complete your tasks.
Power
Pick an electric carving knife that has a motor powerful enough to cut through tough cuts of meat—at least 100 watts of power. A knife with a higher torque ratio also provides more stable cutting power.
Features
Some models come with detachable blades and sharpening tools, while other electric knives require professional sharpening. While most electric knife manufacturers recommend hand washing the blades, some blades are made for the dishwasher. Keep the box to store the electric knife and its blades safely. Before you buy, hold the knife in your hand to determine if it is a comfortable size and weight for you.