Find the recommended drill RPM for a bit and material.
Drill speed depends on both the bit size and the material's recommended cutting speed. Smaller bits and harder materials call for higher and lower RPM respectively. Running a bit at the wrong speed overheats or breaks it, so matching RPM to material avoids ruining expensive drill bits.
Drill Speed (RPM)
RPM = surface speed x 3.82 / bit diameter
RPM = surface speed x 3.82 / bit diameter Drill speed depends on both the bit size and the material's recommended cutting speed. Smaller bits and harder materials call for higher and lower RPM respectively.
Running a bit at the wrong speed overheats or breaks it, so matching RPM to material avoids ruining expensive drill bits.
This calculator takes 2 inputs: Bit diameter, Material. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.