D Drill Size

letter drill

D 0.246 in 6.25 mm

A D drill measures 0.246 in. It taps 1 thread in this chart.

What a D 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 D drill taps, with the percent of thread each one gets and the published chart drill for comparison.
Thread	% thread	Chart drill	Chart %
M7 x 1	57.9%	6 mm	77.0%

Drills either side

C 0.242 in · 6.15 mm Next size down
E 0.250 in · 6.35 mm Next size up

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

D drill: common questions

What size is a D drill?

0.246 inches, which is 6.25 mm. It is a letter drill.

What can I tap with a D drill?

1 thread: M7 x 1 at 57.9%.

What drill is next to a D?

Down: C at 0.242 in. Up: E at 0.250 in.