A mitre box is a tool that is used with a saw to enable you to make precision angled cuts (typically 22.5 degrees, 90 degrees and 45 degrees). Mitre boxes range in size from 12.7mm long by 51mm wide (0.5″ x 2″) to 325mm long by 180mm wide (12.5″ x 7″).
Mitre boxes come in a variety of guises and with a range of features from simple wooden mitre boxes to specialist ones such as the magic mitre box.
A mitre joint is a joint made by cutting two workpieces at specific angles and then joining the two pieces together. The result is a joint that fits together to form a specific angle.Typical 45 degree mitre joints are used on picture frames, skirting boards, and coving to create a neat 90 degree corner.