What Chuck Size Do You Need on a Cordless Drill?
Chuck size is the maximum bit shank diameter the drill can grip, not the tool's overall size. Nearly all current 18V drill/drivers ship with a 1/2-inch keyless chuck.
3/8-inch and 1/2-inch describe the maximum bit shank diameter a drill's chuck can grip, not the tool's overall size. A 1/2-inch chuck accepts larger bits (spade bits, hole saws, large masonry bits) and generally pairs with a higher-torque drill built to drive them; 3/8-inch chucks are common on lighter-duty or older drills and cap out at smaller bit shanks. Nearly all current 18V/20V MAX cordless drill/drivers ship with 1/2-inch keyless chucks, so this distinction matters most when buying bits or comparing to older/budget tools.