With the range of drive sizes, measurement systems, and head types in regular use, a quick reference can save time and prevent damaged hardware. This chart brings those details into one place, showing common socket sizes and how they relate to both inch and metric fasteners, and their corresponding drive sizes.
| Metric (mm) | Imperial (inches) | Drive Size | Common Application |
|---|---|---|---|
| 2mm | 5/64″ | 1/4″ | Electronics, small appliances |
| 2.5mm | 3/32″ | 1/4″ | Electronics, precision devices |
| 3mm | 1/8″ | 1/4″ | Electronics, computer hardware |
| 3.5mm | 9/64″ | 1/4″ | Small machinery, electronics |
| 4mm | 5/32″ | 1/4″ | Furniture assembly, light fixtures |
| 4.5mm | 11/64″ | 1/4″ | Small appliances, toys |
| 5mm | 3/16″ | 1/4″ | Furniture, bicycles, electronics |
| 5.5mm | 7/32″ | 1/4″ | Bicycles, small machinery |
| 6mm | 1/4″ | 1/4″ | Furniture, bicycles, IKEA assembly |
| 7mm | 9/32″ | 1/4″ / 3/8″ | Bicycles, light machinery |
| 8mm | 5/16″ | 1/4″ / 3/8″ | Bicycles, motorcycles, appliances |
| 9mm | 11/32″ | 3/8″ | Motorcycles, machinery |
| 10mm | 3/8″ | 3/8″ | Automotive, motorcycles, appliances |
| 11mm | 7/16″ | 3/8″ | Automotive, motorcycles |
| 12mm | 15/32″ | 3/8″ | Automotive, motorcycles, machinery |
| 13mm | 1/2″ | 3/8″ / 1/2″ | Automotive, spark plugs |
| 14mm | 9/16″ | 3/8″ / 1/2″ | Automotive, suspension bolts |
| 15mm | 19/32″ | 3/8″ / 1/2″ | Automotive, engine components |
| 16mm | 5/8″ | 1/2″ | Automotive, spark plugs |
| 17mm | 11/16″ | 1/2″ | Automotive, wheel lug nuts |
| 18mm | 23/32″ | 1/2″ | Automotive, drain plugs |
| 19mm | 3/4″ | 1/2″ | Automotive, wheel lug nuts |
| 20mm | 25/32″ | 1/2″ | Automotive, heavy machinery |
| 21mm | 13/16″ | 1/2″ | Automotive, wheel lug nuts, axle nuts |
| 22mm | 7/8″ | 1/2″ | Automotive, oxygen sensors |
| 23mm | 29/32″ | 1/2″ | Automotive, axle nuts |
| 24mm | 15/16″ | 1/2″ | Automotive, axle nuts, trucks |
| 25mm | 1″ | 1/2″ | Heavy machinery, trucks |
| 26mm | 1-1/32″ | 1/2″ | Heavy machinery, industrial equipment |
| 27mm | 1-1/16″ | 1/2″ / 3/4″ | Trucks, heavy equipment |
| 28mm | 1-3/32″ | 1/2″ / 3/4″ | Heavy equipment, construction |
| 29mm | 1-1/8″ | 1/2″ / 3/4″ | Heavy equipment, large machinery |
| 30mm | 1-3/16″ | 1/2″ / 3/4″ | Heavy equipment, industrial machinery |
MISUMI USA carries a wide range of socket wrenches for your next project or machine fix. If you have any questions about measurement or sizing, feel free to connect with our product experts, and engineers. Also, if you are looking for more insights be sure to check out our other blog articles, including: 6-Point vs. 12-Point Socket, Socket Wrench Types, and more.
Author: Scott Bredemann | Updated: 12/5/2025
Disclaimer:
The content on this webpage is for informational purposes only. MISUMI makes no guarantees, expressed or implied, regarding the accuracy, completeness, or validity of the information. Performance parameters, tolerances, designs, materials, or processes should not be assumed to reflect third-party suppliers’ or manufacturers’ deliverables within MISUMI’s network. Buyers are responsible for specifying their part requirements