Queen Mattress Specifications. A queen-sized mattress is longer and wider than a full or double mattress, as are its sheets. A queen mattress is 60 inches wide, 80 inches long requiring a fitted Dimensions. Both full beds and twin beds are 75 inches (191 cm) long. They differ when it comes to width, however. At 54 inches (137 cm) wide, a full size bed is nearly as wide as a queen size bed.Twin beds are much narrower, measuring a mere 39 inches (99 cm) across. Buy Bedsure Mattress Pad Full Size Hypoallergenic – Antibacterial, Breathable – Ultra Soft Quilted Mattress Protector, Fitted Sheet Mattress Cover White: Mattress Pads – Amazon.com FREE DELIVERY possible on eligible purchases A full mattress provides a good compromise between twin and queen mattresses. Teens who have outgrown their childhood beds will welcome the added space, while young graduates appreciate the economical price and size when trying to outfit smaller apartments. Invest in comfortable, restful sleep for your family with mattresses that suit individual sleeping styles and preferred levels of firmness. Overstock.com – Your Online Bedroom Furniture Store! Get 5% in rewards with Club O! – Full Size Mattresses .