Nearest Drill Size Finder

Enter a diameter or designation. BenchReference compares it against all standard drills at full precision — never rounding first — and ranks each system's candidates by absolute difference.

Accepts millimeters (), decimal inches (), fractions (), number drills (), and letter drills (). Bare decimals ≤ 1.05 are read as inches, larger as millimeters.

Data provenance. ASME B94.11M, Twist Drills (standard drill size series) (ASME). Differences are computed on full-precision dimensions (1 in = 25.4 mm exactly). See all data sources.