You measure a split topper on four points: width, length, height and split length. That last one is often forgotten, even though it determines whether a split-topper fitted sheet sits neatly and both sides of your adjustable bed can move freely. Always measure the topper itself, not just the size of your box spring or bed frame.
The good news is that measuring only takes a few minutes. With a flexible tape measure and the steps below you will quickly know your split topper size and which fitted sheet matches it.
Exactly what to measure
For a good fit you need more than just the standard size. Write down these four measurements:
- the total width of the split topper
- the total length of the split topper
- the height or thickness of the topper
- the split length at the top
If your topper has a split on both sides, for example on a dual adjustable bed, check whether you need a double split fitted sheet as well.
Measure your split topper in 4 steps
1. Measure the width and length of the topper
Width
Place the measuring tape from the left edge to the right edge of the topper. Measure the topper itself, not the underlying mattress or the bed frame. Common widths are 140, 160 and 180 cm, but don’t rely blindly on what you think you have.
Length
Then measure from the top edge to the bottom edge. Most split toppers are 200 or 210 cm long. You often see 210 cm with luxury box springs and longer beds. A 200 cm fitted sheet on a 210 cm topper usually pulls too tight and pops off the corners more easily.
2. Measure the topper height
Height is often forgotten, but it is important for the fit. Measure the topper from bottom to top while it lies flat on the bed. This measurement determines whether the fitted sheet’s corner height is sufficient. If your topper is 8 cm high, choose a split-topper fitted sheet that is explicitly suitable for that topper height or a bit more. This prevents the fabric from becoming too tight or from sagging.
3. Measure the split length
Measure straight down from the top edge of the topper to the point where the split ends. This is the measurement that most often goes wrong. On many models the split length is around 80 to 90 cm, but it varies by brand and bed type. If the split in the fitted sheet is too short, the head end cannot move up properly. If it is too long, you will get creases faster or a loose fit in the middle.
4. Check whether you have a single or double split
Most split toppers only have a split at the top. Some adjustable beds need a double split at both the top and bottom. So take a good look at your topper’s shape before you order. Want to be sure which version you need? Read: Split topper or double split: what’s the difference?.
Common measurement mistakes
- You measure the bed or mattress instead of the topper itself.
- You only look at 160x200 or 180x200 and forget the topper height.
- You confuse a regular topper with a split topper.
- You estimate the split length without actually measuring it.
- You don’t check whether the fitted sheet is for a single or double split.
Torn between two sizes? Always check the product info for the fitted sheet first. It usually lists the topper height and split length it’s designed for.
Which size split topper fitted sheet do you need next?
Once you’ve noted all the measurements, you can choose with confidence. The fitted sheet size should match your topper’s width and length, and the corner height and split length also need to fit. Only then will the fitted sheet stay smooth, comfy, and practical on an adjustable electric bed.
| Split topper size | Often fits with | Extra things to watch out for |
|---|---|---|
| 140 x 200 cm | compact double beds | check the split length and topper height |
| 160 x 200 cm | standard double box springs | make sure you pick a true split topper fitted sheet, not a regular topper fitted sheet |
| Split topper fitted sheets 180x200 | wide double beds | pay extra attention to a neat fit in the middle |
| 160 or 180 x 210 cm | extra long beds | 200 cm is usually too short here |
Did your measurements show your topper doesn’t have a split? Then choose a non split option, like Topper fitted sheet 180x200 (no split).
The material of the fitted sheet matters too. Jersey and other stretchy fabrics are a bit more forgiving with small size differences, while less elastic fabrics need a more precise fit. Want to compare different fabrics and sizes? Check out the overview of All fitted sheets.
The difference between a topper and a split topper
The difference between a topper and a split topper is the notch at the top. A regular topper is one piece and is meant for a flat or non independently adjustable surface. A split topper has a split so both halves of an electric adjustable bed can move up separately. That is why you also need a special split top sheet. A normal topper fitted sheet restricts movement or pulls at the split. Want more background and practical examples? Read: What is a split topper and who is it useful for?.
Frequently asked questions about measuring split toppers
What size split topper do I need?
You only know for sure once you measure the topper yourself. Note the width, length, height and split length. The most common sizes are 140x200, 160x200 and 180x200, but 210 cm length is also common.
Can I use a regular topper fitted sheet?
No. For a split topper you need a fitted sheet with a split that matches your topper. Otherwise the sheet can pull tight, shift or block the adjustable sections.
What is the ideal thickness for a topper?
It varies per person and per mattress, but many toppers are roughly between 6 and 10 cm. For measuring, it is most important to note the real height so the corner height of the fitted sheet is correct.
Does every split topper fit every adjustable bed?
No. Besides the overall size, the split length also has to match the bed. Some models even need a double split. So always check both the measurements and the split type.
What makes a good split topper?
A good split topper matches your bed size, has the right split for your adjustable system and gives you the comfort you like. So don’t just look at material and thickness, but also at the exact dimensions.
Spend a few minutes measuring and save yourself a lot of hassle later. A well fitting split top sheet stays neater, feels nicer and makes your bed quicker to make. That is exactly the kind of sleep comfort that makes you happy every night.
