fractional-inch drill · nominal diameter
31/64
drill bit size.
A 31/64 bit measures 0.4844 in across (12.303 mm).
The fractional diameter is exact; decimal and metric values are conversions.
Calibrated relative diameter · 1 in reference
31/64 · fractional
0.4844 in
12.303 mm Designation31/64fractional
Inch decimal0.4844nominal
Metric conversion12.303millimetres
Where this size sits from 0 to 1 inch 31/64 · 12.303 mm on a zero to 25.4 millimetre scale. Neighbor marks: 12.3 mm, 12.4 mm.
Measured neighbors
What sits beside 31/64.
“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.
Fractional sizes are exact rational multiples of one inch.
Open source record