Operator script (click here to toggle)

The test passes if the top three lines (user units, px, em) are the same length, the fifth line (%) is the same length as the top three lines, and the bottom five lines (in, cm, mm, pt, pc) are the same length. The fourth line (ex) may have any non-zero length, since the X-height of the font will depend on the exact font chosen by the user agent (which may vary).