Converting a queen size bed to a king size bed is a great way to save money and get a bed upgrade at the same time. A king size bed in the United States measures 76 inches by 80 inches, and a queen size bed measures 60 inches by 80 inches. This means that the only thing you need to change to convert your queen bed into a king is the width of the headboard and foot board. If your bed frame is made of wood, you can cut a new headboard and foot board to expand your frame.
How to Convert a Queen Bed to a King Bed
Remove the headboard and foot board and detach any slats or supports running horizontally across the bed frame.
Measure the points where the headboard and foot board connect to the bed posts. In most wooden bed frames, these will slide into a notch in the bedpost or they will be bolted into place. If they slide into a notch, carefully measure the height, width and depth of the notch.
If you are sliding the headboard into a notch in the post, add the depth of the notch (in inches) to 76 inches; this is the standard width for a king size bed and your total will be the length of your headboard and foot board.
Using a table saw or circular saw, cut the headboard and foot board to the appropriate length and height. The height should be identical to that of your previous headboard and foot board.
If the groove you are sliding the headboard into is smaller than the board you have selected, you will need to trim the end of the board to fit the groove. Using your pencil, mark off the depth and diameter of the groove. Cut the board to size using a jigsaw or table saw.
Sand the edges of your headboard and foot board so that they slide into place smoothly. If necessary, screw into place using your drill.
Measure the distance from the inside of one sideboard to the other. This should be slightly under 76 inches, depending on the depth of the sideboard. Cut slats to this length and screw into place using the screws or bolts from your previous slats.