A planer is a woodworking tool used to shave wood down to a smooth, even thickness and create flat, parallel surfaces. It’s commonly used to clean up rough lumber before building furniture, cabinets, trim, or other wood projects.

What it does

  • Removes thin layers of wood from the surface.
  • Makes boards a consistent thickness.
  • Helps create flatter, smoother surfaces for better fit and finish.

Why people use it

A planer is useful when lumber comes rough, uneven, or slightly warped. It helps woodworkers turn that stock into boards that are easier to join, glue, and finish.

Simple example

If you have a rough board that measures 1 inch in one spot and 15/16 inch in another, a planer can trim the high spots so the whole board ends up more uniform.

If you want, I can also explain the difference between a planer and a jointer.