Tapping Drill Sizes for UNF Threads

The following tables show the range of drill sizes suitable for tapping UNF (Unified National Fine) screw threads.

The first table gives general information about UNF threads - the thread angle, and, for each size, the nominal diameter and thread pitch.

Please also read the general comment on the Tapping Index page.

UNF table UNF tapping 1 UNF tapping 2 UNF tapping 3 UNF tapping 4 UNF tapping 5 UNF tapping 6 UNF tapping 7 UNF tapping 8 UNF tapping 9