What Is a Router Bit?
A router bit is an accessory for a woodworking router. A collet on the router secures the bit to the tool, allowing you to cut mortises for hardware and inlays or add decorative edges to a woodworking project. Router bits come in a range of shapes and sizes to make cuts of different depths and shapes, known as profiles. You can purchase router bits individually or in a router bit set with different shapes and sizes. If you’re new to woodworking and routing, a bit set is a good way to get started.
Not sure which router is best for your projects? Our guide to different types of woodworking routers helps you choose.
Key Parts of a Router Bit
- Shank: The shaft that fits to the router collet, securing the bit to the tool
- Body: A component that supports the cutters and adds weight to create torque for cutting
- Pilot Bearing: A wheel on some bits that guides the bit and keeps it parallel to the workpiece
- Cutters: Blades that remove material and shape the workpiece
Router bits typically have carbide-tipped blades. The carbide material helps keep the blades sharp. You might find some high-speed steel (HSS) bits. They’re less expensive but don’t stay sharp as long as carbide-tipped bits.
Carbide material is brittle, so handle and store your bits carefully. Clean them regularly to remove resin buildup.
Router Bit Sizes
The router bit size is the diameter of the bit shank and must match the collet size of the router. Most router bits have either a 1/4-inch shank or a 1/2-inch shank. Make sure you purchase bits that fit your router.
1/4-Inch Router Bits Are Less Expensive
1/4-inch router bits are more economical to purchase and can do some detail work but create more vibration and don’t cut as cleanly as 1/2-inch bits. Trim routers and other compact router models typically use 1/4-inch bits.
1/2-Inch Router Bits Are More Stable
1/2-inch router bits cost more but last longer and are more stable when cutting. It’s easier to get a clean mortise or edge with a 1/2-inch bit. These bits require larger, more powerful routers.
Some larger routers can use both 1/2-inch and 1/4-inch bits.
Router Bit Types
Use these router bit type charts to find the best bit for your work. Different router bits have different uses. The shape of the body and cutters determine how a bit cuts and the profile or edge shape.
Straight Bits and Mortising Bits
Straight bits and mortising bits make cuts with flat edges. For example:
- Straight/mortising bits cut a groove or mortise with flat edges and a flat bottom.
- Hinge mortising bits cut a larger mortise or recess to fit inlays or hardware.
- Spiral bits have a fluted design that improves chip removal, reducing the risk of scorching the workpiece.
Cutting grooves against the grain of a workpiece creates dados, grooves that can support shelves in bookcases or cabinets.
Edge-Forming Bits
As you might guess from the name, edge-forming bits shape the edges of a workpiece. Different bit shapes cut different profiles. While you can find some that cut more decorative profiles, there are three edge-forming bits that are the most common:
- Roundover bits create a curved or rounded edge.
- Chamfer bits create an angled, flat-faced edge.
- Cove bits create a curved, concave edge.
Use edge-forming bits to cut decorative edges on tabletops, frames and shelving, or to reduce sharp edges on a workpiece.
Cabinetry and Joinery Bits
Cabinetry and joinery bits help create strong joints when building cabinets or furniture. Rabbeting, stile-and-rail, and tongue-and-groove bits are common examples:
- Rabbeting bits cut flat rabbets or shoulders to fit corresponding shoulders on a second workpiece.
- Tongue-and-groove bits cut grooved joints with flat edges.
- Stile-and-rail bits come in pairs and cut complementary grooved joints with decorative edges.
These bits are useful in assembling cabinets and drawers as well as frame elements on panel doors and cabinet doors.
Other Router Bits
You’ll see other router bit types that fit specific applications. For example:
- Flush-trim bits are trim router bits that cut different surfaces flush, such as veneer surfaces or laminate on particleboard.
- Core box bits shape a surface rather than an edge, for example, cutting a rounded groove for fluting in a column or door frame.
- V-groove bits also shape a surface, cutting a V-channel for creating grooves in door panels, lettering on signs and more.
Router Bit Safety
- Follow the bit and router manufacturers’ instructions for use and safety.
- Some specialty bits have large cutting surfaces and are only suitable for use with a router mounted to a routing table.
- Wear eye protection and, when necessary, a face shield, respirator and hearing protection.
- Disconnect the router from power before changing bits or adjusting the tool.
Key Takeaways for Choosing Router Bits
Give your woodworking project a professional look, create mortises for hardware and build strong, attractive joints with the right router bits. There are many types and sizes to choose from, so remember these key points:
- The bit size must match the collet size of your router
- 1/4-inch bits cost less, but 1/2-inch bits give better results.
- Straight bits and mortising bits cut grooves, dados and recesses for hardware.
- Edge-forming bits turn a basic edge into an attractive feature.
- Cabinet and joinery bits create strong, beautiful furniture and cabinetry.
Shop Lowes.com for different bit types and sizes or pick up a router bit set so you’re ready for just about any project. Stop by your local Lowe’s to get a closer look at the bits you’re considering and talk to a Lowe’s Red Vest associate about your woodworking project.
Router Bits FAQ
Get tips for using router bits with the answers to these common questions.
What Are Router Bits and What Do They Do?
Router bits are accessories that attach to woodworking routers. Router bits include blades that shape and cut wood workpieces. The size and shape of the bit determine how it cuts. Router bits can cut recesses for hinges, create beautiful edges on tables, cut joints for assembling furniture and more.
How Do I Change a Router Bit?
Unplug the router or disconnect the battery. Immobilize the router spindle with one of the included wrenches and loosen the collet with the other wrench. If your router has a spindle lock button, you just need a wrench for the collet. Remove the attached bit, being careful of the sharp cutter edges. Insert a new bit with the correct shank diameter according to the instructions in your manual. Immobilize the spindle again and retighten the collet.
How Do I Use Router Bits?
Choose a router bit that fits your router and is designed for your work, whether it’s cutting grooves, creating mortises, shaping edges or cutting joints. Make sure you’re not wearing loose clothing or jewelry and tie back long hair. Put on eye protection and any other safety gear. Start the router and move it along the workpiece against the rotation of the bit. Complete the cut and turn the router off.