Mattresses can have a size variance in the range of 1" in either direction. We wanted to design something that would work best with Casper mattresses but also work with other options!
Here are the respective dimensions for the Foundation by size:
Twin Casper: 37.5" x 74" x 7.75"
Twin XL Casper: 37.5" x 79" x 7.75"
Full Casper: 52.5" x 74" x 7.75"
Queen Casper: 59.5" x 79" x 7.75"
King Casper: 75" x 79" x 7.75"
California King Casper: 71" x 83" x 7.75"
