Shop Floor Charts

F Drill Size

A F letter drill is 0.2570" (6.528 mm).

Closest fraction: 1/4 (0.2500", under by 0.0070").

Tap drill for

5/16-18 UNC

Next size down / up

DrillInchmm
6.5 mm0.25596.500
G0.26106.629

Full drill size chart →

Printable PDF version - Drill Size Chart
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