Toolman

#48 drill bit size

0.076 in

1.93 mm · number drill

Inches0.076 in
Millimetres1.93 mm
Nearest metric drill1.9 mm
SystemNumber (#1 to #60)

What #48 means

A bit marked #48 is a number drill, and the number is an index rather than a measurement — the higher the number, the smaller the bit. #1 is 0.228 inches and #60 is 0.04. That is the opposite of the fractional sizes stamped on a home set, which is why a number drill and a fraction of similar appearance can be very different holes.

The same hole in the other systems

Three drill systems overlap across this range and a workshop rarely has all three. The nearest bit of each other kind to #48:

SystemNearest sizeDifference
letterA — 0.234 in0.158 in larger
fractional5/64" — 0.0781 in0.0021 in larger
metric1.9 mm0.03 mm smaller

One of those is within three thousandths of an inch, which is inside the tolerance of most hand-held work — substitute it and nobody will know.

What gets drilled at 0.076 inches

This is circuit-board and small-pin range — component leads, header pins, the holes a hobbyist drills in perfboard. It is also where the smallest machine-screw taps live, so a drill here is as likely to be preparing a thread as clearing a wire.

Either side of it

DrillInchesMillimetres
#510.067 in1.7 mm
#500.07 in1.78 mm
#490.073 in1.85 mm
#480.076 in1.93 mm
5/64"0.0781 in1.98 mm
#470.0785 in1.99 mm
#460.081 in2.06 mm

Frequently asked questions

What size is a #48 drill bit?

0.076 inches, which is 1.93 mm. Number drills run from #1 at 0.228 inches down to #60 at 0.04, getting smaller as the number rises — the opposite of what most people expect the first time.

What is a #48 drill bit in mm?

1.93 mm. A metric index will offer 1.9 mm as the nearest stocked size, which is 0.03 mm smaller — enough to matter when tapping and not enough to matter for a clearance hole.

Is #48 a tapping drill size?

Not for any of the unified threads on this site. It sits between the sizes the standard taps call for, so it is a clearance or pilot drill rather than a tapping one.

What is the next size up from #48?

5/64" at 0.0781 inches — 0.0021 inches larger. Below it is #49 at 0.073.

Other sizes

Every drill size · Tap drill sizes · Metric threads