What is the difference between regular King (or Eastern King) and California King mattress?Updated 2 years ago

A regular King mattress is 78” x 80” while a California King is slightly narrower and longer at 72” x 84”. This mattress was invented by California mattress manufactures in order to make it more difficult for the big, East Coast mattress companies to compete for their business. It hasnothing to do with the fact that people may or may not be skinnier and taller in California.