A standard king size bed is 76 inches wide by 80 inches long. A California king bed measures 72 inches wide by 84 inches long.
A standard king size bed is also sometimes called an Eastern king, and a California king-sized bed is sometimes called a Western king. Two people sleeping on a king size bed get as much room as if each were sleeping on a twin bed. King beds often sit on top of two side-by-side sets of box springs.
The queen-sized bed, which is one size smaller than the king, is 60 inches wide by 80 inches long.