metric comparison size · nominal diameter

4.5 mm
drill bit size.

A 4.5 mm bit measures 0.1772 in across (4.500 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

4.5 mm · metric

0.1772 in
4.500 mm
Designation4.5 mmmetric
Inch decimal0.1772nominal
Metric conversion4.500millimetres
Where this size sits from 0 to 1 inch
4.5 mm · 4.500 mm on a zero to 25.4 millimetre scale. Neighbor marks: #16, #15.
0 25.4 mm

Measured neighbors

What sits beside 4.5 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