If you only measure up to the upper seam the actual bed height could be off by as much as 3 inches.
How to measure a mattress.
Use a tape measure or fabric ruler to do your measuring.
How to measure bed height.
If necessary repeat for box spring.
Mattresses can curve outward on the sides so make sure you re measuring from the widest point on each side of the mattress.
People often assume the upper seam is the top of the mattress it s not.
Measure from the bottom of the foundation not the floor to the top of the mattress.
Make sure the ruler or tape measure flat on the mattress.
String broom or yardstick.
Measure from the left side to the right side of your mattress to get the width.
If necessary repeat for box spring.
Measure the length in inches from the head of the mattress to the foot of the mattress.
Step 1 strip the bed of all bedding.
Always measure the distance from the floor to the top of the surface on which you will place the mattress so you know what you re getting into.
Pull the steel measuring tape so it extends a few inches from its housing.
You will want to measure it from the exact edge step 2 grab a retractable measuring tape.
If necessary repeat for box spring.
You may ask a friend to help you hold the measuring tape if it does not lock into place step 3 keep a pen and paper nearby to write down the measurements for future reference.
Measure the width and the length of the mattress from one outer edge to the other outer edge that is from left seam to the right seam for width and from top head to the bottom foot for the length.
See the diagram below for a handy visual reference you re on a tight budget.
Place the end of the tape so it touches the bottom of the sagging portion of your mattress alongside the string.
Painter s tape only needed if string is used measuring tape or ruler any type of measuring tape can be used but a stiff type such as steel measuring tape is preferable step 1.
You will be able to use these measurements to see what type of bed you have in the next step.
Measure the width in inches of the mattress from side to side.
Any extra materials on top of the mattress may alter your results or make it.
Make sure your mattress is bare while taking the measurement.
The top is the very crown highest point of the mattress.
Remove all bedding from your mattress including sheets pads and foam toppers so you can accurately measure the depression.
Alternatively you can measure a space in your house to see what size bed will fit comfortably.