BenchReference

#2 Drill Bit

Decimal inches 0.2210″
Millimeters 5.613 mm
System Number (wire gauge)

Nearest equivalents in other systems

System Nearest drill Size Difference
Metric 5.6 mm 0.2205″ / 5.6 mm −0.013 mm (−0.0005″)
Fractional inch 7/32″ 0.2188″ / 5.556 mm −0.057 mm (−0.0023″)
Letter A 0.2340″ / 5.944 mm +0.33 mm (+0.0130″)
−0.449 mm+0.449 mm#2#4−0.305 mm#3−0.203 mm#1+0.178 mm7/32″−0.057 mm5.6 mm−0.013 mmA+0.33 mmtick position = true diameter · number neighbors above, equivalents below · window ±0.45 mm
Positive difference = cuts a slightly larger hole than #2. Sizes beyond the window are listed with arrows — they are not close substitutes.

Clearance drill for

Thread Fit
#10-24 UNC normal
#10-32 UNF normal

Neighboring number sizes

Drill Decimal in mm vs #2
#4 0.2090 5.309 −0.305 mm
#3 0.2130 5.41 −0.203 mm
#2 0.2210 5.613 —
#1 0.2280 5.791 +0.178 mm
Data provenance. ASME B94.11M, Twist Drills (standard drill size series) (ASME). Millimeter and inch values are converted with the exact definition 1 in = 25.4 mm; the canonical dimension for this number size is 0.2210″. See all data sources.