Mattress Topper and Mattress Pad Sizes

Key Takeaways

  • Differentiating Toppers and Pads: Although the terms “mattress topper” and “mattress pad” are sometimes used interchangeably, they serve different functions. Mattress toppers are thicker and can significantly alter the firmness of the mattress, while mattress pads are thinner and provide a subtle softness. It is important to use a waterproof mattress protector in addition to the topper or pad to prevent damage.
  • Understanding Mattress Sizes: Standard mattress sizes are consistent in the United States, but slight variations such as twin XL, full XL, Olympic queen, and California king exist. It is essential to measure the length, width, and depth of the mattress before purchasing a topper or pad to ensure a proper fit.
  • Consideration for Non-Standard Sizes: RVs, futons, and oversized mattresses may have different dimensions compared to standard sizes. For these non-standard sizes, it is advisable to consult specific retailers or suppliers that cater to these variations to find suitable toppers or pads.

Adding a topper or pad to your bed can create a cozy and inviting sleep space, but finding the correct size can be a little confusing. In the United States, mattress sizes are standard. For example, a twin mattress always measures 38 inches wide by 75 inches long. However, standard sizes can also have slight variations, such as twin XL, full XL, Olympic queen, and Cal king.

Depth can also be tricky when shopping for a topper or pad because mattress depth varies considerably, from 9 inches to 16 inches. Throughout this article, we break down the sizes and dimensions of mattress toppers and pads. We also offer some helpful suggestions for measuring your bed so you can find the perfect fitting accessories.

Save $150 On Any Mattress

Plus free shipping

Get $150 OFF Mattresses

Mattress Topper vs. Mattress Pad

Before we outline their dimensions, it is helpful first to understand the difference between a mattress topper and a mattress pad. These names are often used interchangeably and may even be referred to as mattress encasements. However, mattress toppers and pads are slightly different. Both accessories can help adjust the firmness of your mattress and create a more comfortable space. They both also secure to the top of your bed and are covered with a fitted sheet.

However, mattress pads are often thinner pieces of material, while toppers are thick layers of foam, typically latex or memory foam, wrapped in fabric. Toppers are capable of creating a noticeable change in firmness, while mattress pads add a slight softness. Mattress pads typically wrap around the bed’s sides for a secure fit, while bed toppers have corner straps or grips that keep them from moving during the night.

Both mattress pads and toppers can change the feel of your sleep space; however, they should not replace your mattress protector. A waterproof protector should always be used in addition to your pad or topper and should sit just beneath it. This lining will keep odor-causing bacteria and dust mites from building up inside your mattress. It also ensures that accidents and spills do not permanently damage the layers of your bed.

Standard Mattress Sizes

Mattress pads and toppers are available in standard U.S. mattress sizes. For example, queen size accessories accommodate a standard queen bed that measures 60 inches wide by 80 inches long. If you know what size mattress you have, be sure to shop for a topper or pad with those measurements. For your convenience, we outline the different mattress dimensions below.

Standard Mattress Sizes

Mattress SizeMattress Dimensions
Crib27.25 inches wide by 51 inches long
Small Single30 inches wide by 75 inches long
Twin38 inches wide by 74 inches long
Twin XL38 inches wide by 80 inches long
Full54 inches wide by 75 inches long
Full XL54 inches wide by 80 inches long
Queen60 inches wide by 80 inches long
California Queen60 inches wide by 84 inches long
Olympic Queen66 inches wide by 80 inches long
King76 inches wide by 80 inches long
California King72 inches wide by 84 inches long

If you don’t know your bed’s size, measure it before purchasing any accessories. To do so, measure from the head to the food of the bed for length. Then, measure from side to side to determine the width. Purchasing the right size ensures your new topper or mattress pad covers the entire bed and doesn’t hang over the sides.

How to Measure Your Mattress Depth

Determining the depth of your mattress is especially important when fitting it for a topper or pad. If the material or corner straps don’t provide complete coverage and a secure fit, mattress accessories may move during the night. Below, we explain how to measure your mattress to find the correct mattress topper and pad size.

Most mattresses have a depth between 9 and 12 inches; however, there is no standard depth. Additional pillow tops (layers of foam or material is sewn to the top of the bed) can increase the thickness up to 16 inches. Measuring the sides of your bed may not tell you the exact thickness because it doesn’t account for the loft. Some mattresses are naturally thinner on the edges than they are in the middle.

To determine the actual mattress depth, place a yardstick or small piece of wood on top of the mattress and one under the bed (above the box spring). Then, measure the distance between the two yardsticks. This gives you an accurate measurement that accounts for the depth on the sides and the middle. Once you know your bed’s depth, you can determine what pocket size your mattress topper or pad should have.

It is best to choose a pocket size 1 inch deeper than your mattress. If your bed is 15 inches thick, select a topper or pad that accommodates a 16 inches mattress depth.

This extra inch makes it easier for you to secure the topper or pad and ensure it doesn’t fit too tight. Accessories with a snug fit often put stress on both the mattress and the topper, causing both to deteriorate quickly. Selecting a slightly larger topper or pad also eliminates the potential need to return the item if it is too small.

Non-Standard Mattress Topper and Pad Sizes

The sizes outlined above are the most common. However, RVs and futons may not fit these exact measurements. Below, we outline the dimensions of non-standard mattresses to help you find a topper or pad that fits correctly.

Recreational Vehicles

Most recreational vehicles (RVs) have some sleeping space. The mattresses designed for these spaces are often variations of standard U.S. sizes. For example, queen RV mattresses are typically 5 inches shorter than a regular queen.

RV mattresses also have curved edges and a lower profile to accommodate the small living space. Before purchasing a topper or pad for your RV bed, be sure to measure the mattress first. RV stores may sell bedding and accessories to fit these different sizes.


Most futon mattresses have one of the standard bed sizes listed above. However, they typically have a low profile that allows them to be folded in half.

Futon chairs also have different dimensions. These mattresses measure 28 inches wide by 54 inches long when in the open position. A futon loveseat or oversized chair measures 38 inches wide by 54 inches long when open. These sizes don’t correspond to one of the standard U.S. sizes, and it can often be challenging to find toppers or pads for them.

The best option is to shop with a futon retailer. They often sell accessories designed explicitly for futons.

Oversized Mattresses

A standard king size mattress measures 76 inches wide by 80 inches long. California king beds are 4 inches narrower than a standard king, but they are 4 inches longer. Taller couples often prefer a Cal king because it offers extra legroom.

In addition to these two king size beds, there are also three oversized options. Oversized kings provide extra comfort to families who co-sleep and larger couples who need more personal space. Finding the right bedding and accessories for these mattresses can be difficult.

In most cases, brands that sell these sizes also sell oversized toppers and pads. Bed topper suppliers can also make custom designs to fit one of these oversized beds. Below, we cover three common oversized mattresses: Texas King, Wyoming King, and Alaskan King mattresses.

Texas King

A Texas king, also called a grand king, measures 80 inches wide by 98 inches long. A Texas king is 4 inches wider than a standard king and 8 inches wider than a Cal king. Plus, these beds are 18 inches longer than a standard king and 14 inches longer than a Cal king. This extra length is ideal for people over 6 feet tall.

Wyoming King

A Wyoming king, also called a San Francisco king, measures 84 inches wide by 84 inches long. The square shape of this size offers 42 inches of personal space per side. This bed is 8 inches wider than a standard king.

Alaskan King

An Alaskan king measures 108 inches wide by 108 inches long. This size is perfect for families who co-sleep with more than one child. With the additional width and length, couples and their children can stretch out and get a comfortable night’s sleep.

Frequently Asked Questions

Will using a mattress topper or pad change the size sheets I need?

Mattress pads are typically thin and do not drastically change the depth of your mattress. Therefore, they do not require a deeper fitted sheet.

The thickness of a topper can vary between 1 to 3 inches. When using a mattress topper thicker than 1 inch, you may need to purchase a large fitted sheet with deeper pockets. However, the size of your flat sheet will not need to change. The size of top sheets are typically standard, so they will not change if the depth of your mattress increases.

What size fitted sheet fits a 12-inch mattress?

If your bed has a depth of 12 inches, your fitted sheet should have a pocket depth of at least 12 inches. In most cases, a 13-inch pocket is the best choice, since it won’t fit too tight. Make sure to change your sheets at least once a week.

What size beds do college dorm rooms have?

Most college dorm rooms have twin XL size mattresses, which measure 38 inches wide by 80 inches long. These beds are 5 inches longer than a standard twin bed. This extra length accommodates taller college students. However, some college dorms may offer full size mattresses instead.

Can two adults sleep comfortably on a full size bed?

A full mattress measures 54 inches wide by 75 inches long. This size has 27 inches on each side of the bed. While two adults may fit on a full size mattress, they may not sleep comfortably. This size does not leave much room for each person to get a good night's sleep.

Most couples prefer a queen bed, which has 30 inches per side. Families who co-sleep typically select a king size bed, which has 38 inches per side. This extra space allows couples and their children to sleep soundly.

How do I know my mattress size?

If you don't know your mattress's size, you should measure it before purchasing any accessories, such as bed sheets, duvet inserts, mattress covers, toppers, or pads. To determine the length and width, measure from the bed to the foot of the bed, then from side to side. To find the width, place a yardstick on top and under the mattress. Then, measure the space between the two yardsticks.

What is the best mattress size for couples?

Couples tend to be most comfortable on a queen or a king size mattress. Both of these beds offer plenty of room for each person to stretch out. Taller couples may prefer a California queen, which is 4 inches longer than a standard queen mattress. California king beds are also 4 inches longer than normal kings, making them suitable for those over 6 feet tall.


A mattress topper or pad can create a more inviting sleep space. These accessories can also help you adjust the firmness of your mattress. If you find your bed is too firm, a soft topper can add a plush feel and more contouring. If your mattress is too soft, a firm topper can offer more support and stability. A topper can also fix a sagging mattress until you’re ready for a new one.

As you shop for a topper or pad, take a quick measurement of the length, width, and depth. The correct size provides the ultimate comfort and ensures your accessories don’t move around during sleep.

This article is for informational purposes and should not replace advice from your doctor or other medical professional.

Andrew Russell, Wellness Writer Andrew Russell

Andrew Russell is a part-time writer and full-time sleep enthusiast. At Zoma, Andrew lends his sleep expertise and writes many of our “better sleep” guides. Outside of Zoma, Andrew puts his advice to the test, always trying new ways to get deeper, more restorative sleep. We appreciate Andrew because he doesn’t give advice that he doesn’t follow himself, so you can feel confident his solutions for better sleep really do the trick. Andrew's work has been featured on Ladders, Bright Side, and several other publications.

View all posts

Leave a Comment

Your email address will not be published. Required fields are marked *

We think you’ll also enjoy…

Go to top