Tap Drill Size Chart

16.8 mm Drill Size

metric drill

16.8 mm 0.6614 in 16.80 mm

A 16.8 mm drill measures 0.6614 in. It taps 2 threads in this chart.

What a 16.8 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 16.8 mm drill taps, with the percent of thread each one gets and the published chart drill for comparison.
Thread % thread Chart drill Chart %
3/4-10 68.2% 21/32″ 72.2%
M18 x 1.5 61.6% 16.5 mm 77.0%

Other jobs for a 16.8 mm

Hard-material tap drill
The size to use in stainless or tool steel for M18 x 1.5, 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 →

16.8 mm drill: common questions

What size is a 16.8 mm drill?
0.6614 inches, which is 16.80 mm. It is a metric drill.
What can I tap with a 16.8 mm drill?
2 threads: 3/4-10 at 68.2%, M18 x 1.5 at 61.6%.
What drill is next to a 16.8 mm?
Down: 16.7 mm at 0.6575 in. Up: 16.9 mm at 0.6654 in.