metric comparison size · nominal diameter
12.4 mm
drill bit size.
A 12.4 mm bit measures 0.4882 in across (12.400 mm).
The metric diameter is the generated reference value; inches are a conversion. Commercial set contents vary.
Calibrated relative diameter · 1 in reference
12.4 mm · metric
0.4882 in
12.400 mm Designation12.4 mmmetric
Inch decimal0.4882nominal
Metric conversion12.400millimetres
Where this size sits from 0 to 1 inch 12.4 mm · 12.400 mm on a zero to 25.4 millimetre scale. Neighbor marks: 31/64, 12.3 mm.
Measured neighbors
What sits beside 12.4 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