Drill Bit Types Explained: Wood, Metal, Masonry, and More

Most drilling problems that look like a tool problem are actually a bit problem. A bit ground for wood will wander and burn in metal, a metal bit will dull almost instantly against brick, and the wrong shank won't even seat in some chucks. Once you know what each bit type is actually built for, picking the right one becomes automatic.

This isn't an exhaustive catalog — it's the handful of bit types that cover the vast majority of home and DIY drilling, plus how to tell them apart at a glance.

Twist bits: the general-purpose default

Twist bits are the ones everyone pictures when they hear 'drill bit' — a straight fluted shaft with a pointed tip. They come in different metals and coatings that determine what they can handle: black oxide and standard high-speed steel (HSS) bits are fine for softwood, plastic, and thin sheet metal, while cobalt and titanium-coated bits hold an edge longer and can push through hardwood and steel.

A basic titanium-coated twist bit set is the single most useful thing to have on hand, since it covers light wood and metal drilling without needing a dedicated bit for every material.

Brad-point bits: cleaner holes in wood

Brad-point bits look similar to twist bits but have a sharp center spur and two cutting wings instead of a plain conical tip. That center point keeps the bit from wandering when you start a hole, and the wings shear wood fibers cleanly instead of tearing them.

They're worth the upgrade over standard twist bits for any woodworking where hole placement and a clean exit are important, like furniture builds, shelving, or dowel joints.

Spade and Forstner bits: bigger holes in wood

Once you need holes larger than about 1/2 inch — for door hardware, plumbing runs, or wiring — twist and brad-point bits aren't the right tool. Spade (paddle) bits are flat, inexpensive, and fast, making them a good choice for rough holes like running cable through studs.

Forstner bits cost more and cut more slowly, but they produce flat-bottomed, very clean holes with minimal tear-out, even at odd angles or near an edge. They're the better choice for visible woodworking, like hinge mortises or hardware installs where the hole quality shows.

Masonry bits: built for brick, block, and concrete

Masonry bits have a carbide tip brazed onto the end of the shaft, which is hard enough to grind through brick, mortar, and concrete block without dulling immediately the way a standard steel bit would. For light masonry drilling, a regular drill with a masonry bit and steady pressure can work.

For anchoring into cured concrete or dense block, a hammer drill or rotary hammer paired with the same style of masonry bit makes a real difference — the hammer action pulverizes material ahead of the bit instead of relying on rotation alone.

Step bits: one bit, many hole sizes in sheet metal

Step bits are the cone-shaped, staircase-profile bits mainly used for thin sheet metal, electrical boxes, and plastic. Each 'step' cuts a slightly larger diameter, so a single bit can drill a whole range of hole sizes cleanly without the bit grabbing or tearing the material, which is a common problem with twist bits in thin sheet stock.

They're a favorite for electrical and HVAC work for exactly that reason — no need to swap bits when a job calls for several different hole sizes in the same panel.

Shank type matters as much as bit type

Most drill bits use a round shank that fits any keyed or keyless chuck. Bits sold for use in impact drivers instead use a 1/4-inch hex shank that locks into a quick-change chuck, letting you swap bits without a keyless collar. Hex-shank bits also work fine in a standard drill with a keyless chuck.

If you're buying bits specifically to use in an impact driver, confirm they're rated for impact use — impact-rated bits are made from tougher steel to handle the rotational hammering without snapping the way a standard bit can.