Toolman

#60 drill bit size

0.04 in

1.02 mm · number drill

Inches0.04 in
Millimetres1.02 mm
Nearest metric drill1 mm
SystemNumber (#1 to #60)

What #60 means

A bit marked #60 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 #60:

SystemNearest sizeDifference
letterA — 0.234 in0.194 in larger
fractional3/64" — 0.0469 in0.0069 in larger
metric1 mm0.016 mm smaller

The closest substitute is 0.0069 inches away. For a clearance hole that is nothing; for a tapping hole it moves the thread engagement by several per cent, which is the difference between an easy tap and a broken one.

What gets drilled at 0.04 inches

Under fifty thousandths of an inch, a drill is watchmaker and model-maker territory: pinning small parts, clearing wire in an instrument, opening a jet. Bits this fine snap if the work moves at all, which is why they are used in a press or a pin vice rather than a hand drill.

Either side of it

DrillInchesMillimetres
1/64"0.0156 in0.4 mm
1/32"0.0313 in0.79 mm
#600.04 in1.02 mm
#590.041 in1.04 mm
#580.042 in1.07 mm
#570.043 in1.09 mm

Frequently asked questions

What size is a #60 drill bit?

0.04 inches, which is 1.02 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 #60 drill bit in mm?

1.02 mm. A metric index will offer 1 mm as the nearest stocked size, which is near enough identical.

Is #60 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 #60?

#59 at 0.041 inches — 0.001 inches larger. Below it is 1/32" at 0.0313.

Other sizes

Every drill size · Tap drill sizes · Metric threads