Router Bit Speed Calculator
Running a router bit too fast or too slow can burn wood, cause chatter, or wear out bits prematurely. Enter your bit diameter and material to get a recommended RPM range.
Recommended Router Speed
—
Bit Diameter (in)—
Base Surface Speed (SFM)—
Adjusted Surface Speed (SFM)—
Recommended RPM—
About this calculator
Calculate the recommended router spindle speed (RPM) based on bit diameter and material to reduce burning, chatter, and tool wear.
Frequently Asked Questions
Why does bit diameter matter for router speed?
Larger diameter bits move faster at the cutting edge for a given RPM, so they need lower spindle speeds to avoid burning the material or losing control.
What happens if I run the bit too fast?
Excess speed can scorch wood, dull bits faster, and increase kickback risk, especially with large-diameter bits.
Should I always use the maximum RPM my router allows?
No. Match RPM to bit diameter and material; many routers have variable speed dials specifically for this reason.