Twist Drill Bit

A twist bit is the most common type of drill bit for home use. It works for general-purpose drilling in wood, plastic and light metal.

Brad-Point Drill Bit

A brad-point bit is designed for boring into wood. The brad at the center of the bit tip helps position the bit precisely for accurate drilling and produces a clean exit point in the workpiece. The flutes — grooves that wrap around the bit and channel away chips and dust — are extra-wide to remove more material.

Auger Drill Bit

An auger bit, another type of wood-boring bit, has a screw tip that starts the hole and pulls the bit through the workpiece to quickly create a clean hole. These bits can be as long as 18 inches. As with the brad-point bit, large flutes help remove chips and dust. An auger bit with a hollow center provides even more chip removal, allowing for deeper boring; one with a solid center is stronger and more rigid.

Self-Feed Drill Bit

A self-feed bit bores through wood. Like the auger bit, a screw at the tip helps position the bit and draws it through the work piece. However, this bit is more compact. It doesn't have the standard flutes of a twist bit, so you need to pull the bit back periodically to clear away chips and dust.

Spade Bit

A spade bit, also known as a paddle bit, bores large-diameter holes — up to 1-1/2 inches in diameter — in wood. It has a flattened blade with a sharp point that helps position and steady the bit. Some spade bits have points at the two edges that help create a neater hole and exit point.

Forstner Drill Bit

A Forstner bit bores smooth, clean holes in wood. You can use it to create flat-bottomed holes — such as for receiving dowels. If you need to bore through the workpiece, it creates a neat exit hole. The design also allows you to overlap holes. A point helps you to position the bit precisely on the workpiece. Pull the bit out regularly to clear away chips and dust as you work. A hand-held drill may not always give you the force or control you need to use a Forstner bit, so a drill press is a better option for some applications.

Hole Saw

A hole saw drills large holes — such as for installing door hardware or creating a pass-through for wiring. A hole saw creates a plug of waste material; a cut-out in the side of the saw cylinder allows you to push it out. Typically, a hole saw attaches to an arbor or mandrel which includes a shank. The arbor also holds a pilot bit for centering and steadying the cutting blade. Some smaller hole saws have a built-in shank and don't use a pilot bit.

A bi-metal hole saw cuts through wood and metal. A hole saw with a carbide edge works on heavier materials such as ceramic tile and masonry. A hole saw with a diamond edge also works on tile and masonry, but cuts faster than carbide models.

Countersink Drill Bit

A countersink bit — also called a screw pilot bit — is a specialty bit for drilling in wood. In a single action, the bit can drill pilot, countersink and counterbore holes, allowing you to countersink a fastener and install a plug over the fastener head.

Plug Cutter

A plug cutter bores holes in wood, creating wood plugs for use in concealing recessed fasteners.

Step Drill Bit

A step bit is designed primarily for drilling in thin — up to 1/4 inch — metal, but will work with wood. The stepped design allows you to use a single bit to drill holes with different diameters. Often the diameter of each step is etched into the bit. You can also use this type of bit to deburr holes, clearing away waste material.

​