Other naming systemsABSOLUTE DIAMETER DELTA
fractional-inch drill · nominal diameter
45/64
drill bit size.
A 45/64 bit measures 0.7031 in across (17.859 mm).
The fractional diameter is exact; decimal and metric values are conversions.
Calibrated relative diameter · 1 in reference
45/64 · fractional
0.7031 in
17.859 mm Designation45/64fractional
Inch decimal0.7031nominal
Metric conversion17.859millimetres
Where this size sits from 0 to 1 inch 45/64 · 17.859 mm on a zero to 25.4 millimetre scale. Neighbor marks: 23/32, 11/16.
Measured neighbors
What sits beside 45/64.
“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