metric comparison size · nominal diameter

5.1 mm
drill bit size.

A 5.1 mm bit measures 0.2008 in across (5.100 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

5.1 mm · metric

0.2008 in
5.100 mm
Designation5.1 mmmetric
Inch decimal0.2008nominal
Metric conversion5.100millimetres
Where this size sits from 0 to 1 inch
5.1 mm · 5.100 mm on a zero to 25.4 millimetre scale. Neighbor marks: #7, #8.
0 25.4 mm

Measured neighbors

What sits beside 5.1 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