Generally, the TSA and most international aviation authorities prohibit the majority of hand tools in carry-on luggage due to safety concerns. Specifically, tools that are longer than 7 inches (18 cm) from end to end are strictly forbidden and must be placed in checked baggage. This includes items like heavy-duty wrenches, hammers, and large screwdrivers. Furthermore, any tools with sharp edges or points, such as saws, box cutters, or drills (including cordless ones), are never allowed in the cabin regardless of their size. However, small, non-sharp tools like tiny screwdrivers or pliers under the 7-inch limit may be permitted at the discretion of the security officer. In 2026, with the rollout of advanced CT scanners at many airports, security is more precise, but the "length and sharpness" rule remains the global standard. If you are a technician or DIY enthusiast, it is always safest to check your toolbox to avoid having expensive equipment confiscated at the checkpoint.