Which sizes are offered in the Purple® Mattress? We know you're going to love your Purple® Mattress! Find all our sizes HERE. Related articles Mattress Dimensions What is the correct direction for the Purple® Mattress to lay? I need a mattress that will help prevent pressure sores. Will your mattress help? Can the Purple® Mattress be without a platform? Should I use a box spring with my Purple® Mattress?