BenchReference / Drill sizes / 13.5 mm 13.5 mm Drill Decimal inches 0.5315″
Millimeters 13.5 mm
System Metric
Nearest equivalents in other systems System Nearest drill Size Difference Fractional inch 17/32″ 0.5313″ / 13.494 mm −0.006 mm (−0.0002″)
Number (wire gauge) #1 0.2280″ / 5.791 mm −7.709 mm (−0.3035″)
Letter Z 0.4130″ / 10.49 mm −3.01 mm (−0.1185″)
−1.08 mm +1.08 mm 13.5 mm 12.9 mm −0.6 mm 13 mm −0.5 mm 14 mm +0.5 mm 14.5 mm +1 mm 17/32″ −0.006 mm ← #1 −7.709 mm ← Z −3.01 mm tick position = true diameter · metric neighbors above, equivalents below · window ±1.08 mm
Positive difference = cuts a slightly larger hole than 13.5 mm. Sizes
beyond the window are listed with arrows — they are not close substitutes.
Clearance drill for Neighboring metric sizes Drill Decimal in mm vs 13.5 mm 12.9 mm 0.5079 12.9 −0.6 mm 13 mm 0.5118 13 −0.5 mm 13.5 mm 0.5315 13.5 — 14 mm 0.5512 14 +0.5 mm 14.5 mm 0.5709 14.5 +1 mm
← 13 mm (smaller) 14 mm (larger) →
Compare 13.5 mm with another size
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 metric size is 13.5 mm. See all data sources .