metric comparison size · nominal diameter

3.4 mm
drill bit size.

A 3.4 mm bit measures 0.1339 in across (3.400 mm).

The metric diameter is the generated reference value; inches are a conversion. Commercial set contents vary.

Diameter conversion verified
Calibrated relative diameter · 1 in reference

3.4 mm · metric

0.1339 in
3.400 mm
Designation3.4 mmmetric
Inch decimal0.1339nominal
Metric conversion3.400millimetres
Where this size sits from 0 to 1 inch
3.4 mm · 3.400 mm on a zero to 25.4 millimetre scale. Neighbor marks: #29, 3.3 mm.
0 25.4 mm

Measured neighbors

What sits beside 3.4 mm.

“Nearest” means nominal diameter only. It does not make a neighboring size acceptable for a tolerance, tapping, reaming, or fastener application.

Source record

Drill Bit Size Chart.

A generated comparison series from 0.5 to 13.0 mm in 0.1 mm steps. It is not a claim that every size is included in every commercial set.

Open source record