How do you measure the blade length of a knife? It seems that measuring a blade would be straightforward, but varying designs and construction can cause confusion about where to start the measurement. This results in issues when different manufacturers offer models that vary in size, as well as when law enforcement officers are measuring a knife to determine if it fits within the laws for a particular jurisdiction.
To clear up the confusion, the American Knife and Tool Institute (AKTI) has released an educational video on “How to Measure a Knife Blade,” which is available above, on the Institute’s YouTube channel or at youtu.be/nmCiHRhO-bw.
The 1:42 video clearly explains how to use common measuring tools like a ruler or tape measure to determine the official length of a blade, using a standard that AKTI has promoted within the industry and to law enforcement for more than 11 years. This video, or written guidelines on AKTI.org, can be used to establish a proper measurement for any knife blade.
Recommendations in the video include:
- Measure your blade using the shortest straight line from the tip of the blade to the forwardmost part of the handle.
- Round the measurement down to the nearest 1/8-inch increment.
If there is still confusion about the length of the blade, such as when the handle is angled or the tip of the knife blade extends to a point, AKTI recommends using the shortest measurement that can be made.
The “How to Measure a Knife Blade” video is one of three prepared by the AKTI Education Committee. Other topics include “My First Knife” and “Knife Safety and Maintenance Tips.” All the videos can be viewed on AKTI’s YouTube channel. AKTI provides additional resources for knife owners and law enforcement officials on its website, AKTI.org.