What length should a 16-gauge extension cord be for a 10-amp tool?

Keep a 16-gauge extension cord under 50 feet for a 10-amp tool, and even that is pushing it. At 100 feet, voltage drop loses almost 20 volts on a 120V circuit, making the tool run sluggish, overheating the cord, and potentially tripping breakers. For anything over 25 feet at 10 amps, go with a 14-gauge cord instead.