Most people know the size of their mattress, i.e., king, queen, full or twin, but determining depth is a little trickier. Some mattress are also extra long. The following steps will let you quickly and easily figure out the exact size of your mattress.
What you will need:
- Two pieces of cardboard.
- A ruler or tape measure or a standard 8 1/2 x 11 piece of paper.
Measuring the depth of a mattress:
- Place one piece of cardboard between the mattress and box spring having it stick out a few inches. Do this in the middle of one of the sides of the mattress, not at a corner.
- Place the second piece of card board on top of the mattress at the same spot.
- Use a tape measure to determine the space between the card board pieces. If you don’t have a tape measure, continue to step 4.
- Hold a piece of paper, the long way, up to the pieces of cardboard. The paper is the size of a standard mattress. If it fits just right, then you have an 11 inch mattress. If there is a big gap, then it is most likely a 15 inch mattress. If it does not fit, turn the paper the other way. If it fits with just a tiny gap, you have a 9 inch mattress. If there is a larger gap, then you likely have a 6 inch mattress.
Is my mattress extra long?
While not common, some full and twin mattresses are extra long. Extra long mattress are 5 inches longer then a standard mattress. To measure for an extra long mattress, do the following:
- If you have two people, have one person hold the piece of card board at the head of the bed, against the side of the mattress. If you are doing this by yourself, push the bed to the head of the mattress if it’s against the wall or tightly against the head board.
- Use your tape measure to measure from the card board to long edge of the bed. It is a good idea to use a piece of card board at the foot as well, since the bed is likely rounded on the edges. If you don’t have a tape measure go to the next step.
- Using seven sheets of standard paper, lay six of the sheets of paper end to end on the bed, the long way, between the pieces of card board. Then put the last piece the short way. If the last sheet just about reaches the end of the bed, your have a standard 75 inch mattress. If there is a gap about the width of your hand, then you have an 80 inch mattress. If the gap is almost the size of another sheet of paper put down the short way, then you have an extra, extra long mattress. This method only applies to twin and full size mattresses.