BenchReference / Drill sizes / 1.3 mm 1.3 mm Drill Decimal inches 0.0512″
Millimeters 1.3 mm
System Metric
Nearest equivalents in other systems System Nearest drill Size Difference Fractional inch 3/64″ 0.0469″ / 1.191 mm −0.109 mm (−0.0043″)
Number (wire gauge) #55 0.0520″ / 1.321 mm +0.021 mm (+0.0008″)
Letter A 0.2340″ / 5.944 mm +4.644 mm (+0.1828″)
−0.15 mm +0.15 mm 1.3 mm 1.2 mm −0.1 mm 1.25 mm −0.05 mm 1.4 mm +0.1 mm 3/64″ −0.109 mm #55 +0.021 mm 1.5 mm +0.2 mm → A +4.644 mm → tick position = true diameter · metric neighbors above, equivalents below · window ±0.15 mm
Positive difference = cuts a slightly larger hole than 1.3 mm. Sizes
beyond the window are listed with arrows — they are not close substitutes.
Neighboring metric sizes Drill Decimal in mm vs 1.3 mm 1.2 mm 0.0472 1.2 −0.1 mm 1.25 mm 0.0492 1.25 −0.05 mm 1.3 mm 0.0512 1.3 — 1.4 mm 0.0551 1.4 +0.1 mm 1.5 mm 0.0591 1.5 +0.2 mm
← 1.25 mm (smaller) 1.4 mm (larger) →
Compare 1.3 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 1.3 mm. See all data sources .