1.8 mm Drill Size

metric drill

1.8 mm 0.0709 in 1.80 mm

A 1.8 mm drill measures 0.0709 in. It taps 2 threads in this chart.

What a 1.8 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 1.8 mm drill taps, with the percent of thread each one gets and the published chart drill for comparison.
Thread	% thread	Chart drill	Chart %
#2-64	74.4%	#50	78.8%
#2-56	65.1%	#50	69.0%

Other jobs for a 1.8 mm

Form-tap hole: The published roll-tap hole for M2 x 0.4. A form tap displaces metal instead of cutting it, so it needs this larger hole.

Drills either side

#50 0.070 in · 1.78 mm Next size down
1.85 mm 0.0728 in · 1.85 mm Next size up

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

1.8 mm drill: common questions

What size is a 1.8 mm drill?

0.0709 inches, which is 1.80 mm. It is a metric drill.

What can I tap with a 1.8 mm drill?

2 threads: #2-64 at 74.4%, #2-56 at 65.1%.

What drill is next to a 1.8 mm?

Down: #50 at 0.070 in. Up: 1.85 mm at 0.0728 in.