Key gauge is a specialised tool used primarily in the locksmithing and security sector for measuring and decoding the configurations of keys and locks. This device assists professionals in creating replicas of keys without needing the original key, facilitating lock repair and maintenance. It operates by measuring the depth of cuts on a key, which are essential for matching the pin settings in a corresponding lock cylinder.
Key gauges are often manufactured from metal or high-strength plastic and feature precise scale markings that conform to specific key blank profiles used across various lock systems. Some key gauges are universal, designed to work with multiple types of keys, while others are specific to certain brands or types of locks, such as automotive, padlock, or door lock systems. The accuracy of a key gauge is paramount in ensuring the effectiveness of the duplicated or repaired key, as even minor discrepancies can render a key unusable.
In professional settings, the use of a key gauge can drastically improve the efficiency of locksmithing tasks, reducing guesswork and minimising the risk of damage to lock mechanisms during key fitting. The tool's design typically allows for easy portability and durability, making it an indispensable part of a locksmith's toolkit.