No, all toilet seats do not fit all toilets. There are various sizes and shapes of toilets, so there are also multiple sizes and shapes of toilet seats.  Toilet seats are typically made to fit one specific size or shape of a toilet. So, when shopping for a toilet seat, it is vital to know the size and shape of your toilet. Standard, extended, and round toilet seats are available. An elongated toilet seat is about two inches longer than a standard seat and will fit most toilets. A round toilet seat is smaller and might be a good choice for a compact bathroom or if you have small children. That way, you can select a seat that will fit properly and comfortably.  To make your seat more comfortable, use these tricks.