What is the exact conversion factor used to define one inch in millimeters as per the 1959 international agreement?
Show answer
25.4 mm
Before 1959, the US and UK used slightly different definitions for the inch. The International Yard and Pound Agreement standardized the inch as exactly 25.4 millimeters to ensure industrial and scientific interoperability.
Also asked as:
- According to the 1959 international agreement, how many millimeters are exactly equal to one inch?