In America, the standard sizes for bed sheets are twin, full, queen and king. Other bed sheet sizes are twin XL, which are longer than standard twin, and California king, which are longer and not as wide as standard king.
Twin bed fitted sheets measure 39 inches by 75 inches, and the flat sheets measure 66 inches by 96 inches. Twin XL fitted sheets are 39 inches by 80 inches, and the flat sheets are 66 inches by 102 inches. Full-size sheets are the same length as twin sheets, but the width of the fitted sheet is 54 inches and the width of the flat sheet is 80 inches.
Queen and king sheets are the same length as twin XL sheets. Queen sheet widths are 60 inches for the fitted sheet and 90 inches for the flat sheet. King sheet widths are 76 inches for the fitted sheet and 108 inches for the flat sheet. California king flat sheets have the same dimensions as standard king, but the fitted sheet is 72 inches by 84 inches.
Mattresses come in heights ranging from 7 inches to 22 inches. Consumers should check the dimensions on the packaging for new sheets to ensure they will fit their mattress's height.