Tap Drill Size Chart

20 mm Drill Size

metric drill

20 mm 0.7874 in 20.00 mm

A 20 mm drill is the standard tap drill for M22 x 2.

What a 20 mm drill taps

Every thread this drill cuts between 50% and 85% of thread, deepest first. Outside that band it is the wrong drill for the job, so nothing below that line is listed.

Threads a 20 mm drill taps, with the percent of thread each one gets and the published chart drill for comparison.
Thread % thread Chart drill Chart %
M22 x 2 chart drill 77.0% 20 mm 77.0%
M22 x 2.5 61.6% 19.5 mm 77.0%
7/8-9 60.7% 49/64″ 75.8%

Other jobs for a 20 mm

Hard-material tap drill
The size to use in stainless or tool steel for M22 x 2.5, where it leaves a shallower thread than the standard drill and cuts tapping torque.

Drills either side

All drill sizes → · Open this drill in the calculator →

20 mm drill: common questions

What size is a 20 mm drill?
0.7874 inches, which is 20.00 mm. It is a metric drill.
What can I tap with a 20 mm drill?
3 threads: M22 x 2 at 77.0%, M22 x 2.5 at 61.6%, 7/8-9 at 60.7%.
Is a 20 mm drill the standard tap drill for anything?
Yes, for M22 x 2 (77.0% thread). That is the size published tap and drill charts give.
What drill is next to a 20 mm?
Down: 19.9 mm at 0.7835 in. Up: 51/64 in at 0.7969 in.