Processes - Machining

The drill size chart provides a comprehensive list of standard size drill bits in several measurement systems, including fractional, metric, wire gauge number, and letter. The decimal equivalents of the diameters are shown in both English and Metric units. Fractional sizes are measured in inches, while metric sizes are measured in millimeters. The wire gauge numbers (#1-#107) decrease in size as numbers increase, and letter designations (A-Z) increase in size from A to Z. The drill size chart contains tools from the smallest wire gauge sizes up to 1.5 inches (38.1 mm) in diameter, covering the most commonly used drill bit sizes in manufacturing and fabrication.