BenchReference / Drill sizes / 6.9 mm 6.9 mm Drill Decimal inches 0.2717″
Millimeters 6.9 mm
System Metric
Nearest equivalents in other systems System Nearest drill Size Difference Fractional inch 17/64″ 0.2656″ / 6.747 mm −0.153 mm (−0.0060″)
Number (wire gauge) #1 0.2280″ / 5.791 mm −1.109 mm (−0.0437″)
Letter I 0.2720″ / 6.909 mm +0.009 mm (+0.0003″)
−0.552 mm +0.552 mm 6.9 mm 6.7 mm −0.2 mm 6.8 mm −0.1 mm 7 mm +0.1 mm 7.1 mm +0.2 mm 17/64″ −0.153 mm I +0.009 mm ← #1 −1.109 mm tick position = true diameter · metric neighbors above, equivalents below · window ±0.55 mm
Positive difference = cuts a slightly larger hole than 6.9 mm. Sizes
beyond the window are listed with arrows — they are not close substitutes.
Neighboring metric sizes Drill Decimal in mm vs 6.9 mm 6.7 mm 0.2638 6.7 −0.2 mm 6.8 mm 0.2677 6.8 −0.1 mm 6.9 mm 0.2717 6.9 — 7 mm 0.2756 7 +0.1 mm 7.1 mm 0.2795 7.1 +0.2 mm
← 6.8 mm (smaller) 7 mm (larger) →
Compare 6.9 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 6.9 mm. See all data sources .