metric comparison size · nominal diameter
10.2 mm
drill bit size.
A 10.2 mm bit measures 0.4016 in across (10.200 mm).
The metric diameter is the generated reference value; inches are a conversion. Commercial set contents vary.
10.2 mm · metric
Where this bit is specified
What 10.2 mm is for.
10.2 mm is the cutting-tap drill for the thread below— usually the reason this size gets looked up. Engagement is calculated from the basic 60° profile; open a thread for its published row, evidence, and limits.
Measured neighbors
What sits beside 10.2 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