M Drill Size

letter drill

M 0.295 in 7.49 mm

A M drill measures 0.295 in. It taps 1 thread in this chart.

What a M 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 M drill taps, with the percent of thread each one gets and the published chart drill for comparison.
Thread	% thread	Chart drill	Chart %
M8 x 0.75	52.0%	7.3 mm	71.9%

Other jobs for a M

Form-tap hole: The published roll-tap hole for 5/16-24. A form tap displaces metal instead of cutting it, so it needs this larger hole.

Drills either side

7.4 mm 0.2913 in · 7.4 mm Next size down
O 0.316 in · 8.03 mm Next size up

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

M drill: common questions

What size is a M drill?

0.295 inches, which is 7.49 mm. It is a letter drill.

What can I tap with a M drill?

1 thread: M8 x 0.75 at 52.0%.

What drill is next to a M?

Down: 7.4 mm at 0.2913 in. Up: O at 0.316 in.