What Mattress Thickness Should I Buy?

Written by
Purple Staff
Last Updated
May 16, 2023
min read

A comfortable mattress is essential for restful sleep, but picking the right one isn't as easy as it sounds. You have to consider your sleeping position, body weight, and preferred firmness level. While keeping in mind how mattress thickness ties into each of these considerations.

In this guide, we'll help you understand how mattress thickness affects your comfort. Provide you with the information you need to know to be confident in choosing the right mattress thickness for you

We'll also share information on the types of mattresses available at Purple. Purple provides a variety of mattress thickness options for unique needs.

What Is Mattress Thickness?

The term “mattress thickness” is the same as the “mattress height” and “mattress depth.”

Mattress thickness should not be confused with size. Bed sizes are determined by the horizontal dimensions (i.e. width and length). The height or thickness of a mattress depends on the model.

For any given model, every size has the same thickness – no matter if it's a twin-size, queen-size, or full-size mattress.

Purple Mattress Thickness

At Purple, we have nine types of mattresses, each with a different thickness.



Purple NewDay Mattress


The Purple Mattress


Purple Plus Mattress


Purple Restore


Purple RestorePlus


Purple RestorePremier


Purple Rejuvenate 


Purple RejuvenatePlus


Purple RejuvenatePremier


purple mattress thickness for Newday-Purple Restore Plus
purple mattress thickness for rejuvenate mattresses

As a general rule, when mattresses are made from the same materials, the thinner the mattress, the firmer it is. Conversely, the thicker it is, the softer it becomes. Hybrid mattresses are usually thicker than their all-foam counterparts to allow for coil height.

Why Choose Purple Mattresses?

Purple mattresses are unique, thanks to the patented Purple GelFlex Grid. This grid adapts instantly as you move, so you can roll or shift uninterruptedly as you sleep. It's also designed to be both soft and supportive, exactly what you need for a comfortable night.

Meanwhile, the Hyper-Elastic Polymer material provides you with the comfort and the support you need. It conforms when pressure is applied, then returns to shape immediately after. That way, you can wake up without hip or shoulder pain from the night before.

What Is The Ideal Mattress Thickness For You?

To pick the most appropriate mattress thickness, consider your sleeping position, body type (size and weight), and preferred firmness levels.

Sleeper Types

Always pick a mattress based on your sleeping position. Here are some sleeping positions and the appropriate mattresses for each:

  • Side sleeper: Choose a thicker, softer mattress that will let your hips and shoulders sink into the foam. In general, it's best to choose 10 to 12” thick mattresses.
  • Back sleeper: Pick a medium-firm or firm mattress with average thickness. This keeps your spine aligned while you sleep.
  • Stomach sleeper: Choose a firmer mattress with average thickness. This will keep your hips from sinking and prevent lower back pain.
  • Combination sleeper: Combination sleepers are comfortable with thicker mattresses with medium firmness. They need a good balance between firmness and softness since they tend to switch positions as they sleep.

Body Size And Weight

Aside from sleeping position, always consider your body weight. Here is the appropriate mattress thickness for each:

  • Lightweight people (130 pounds or less): Pick a mattress with thicker comfort layers. This will help relieve pressure points and prevent body pain.
  • Average weight people (130-230 pounds): Choose any thickness based on your sleeping position.
  • Taller and heavier people (230 pounds and above): Pick firmer mattresses with thick comfort layers. This should provide ample support for your body.

Firmness Levels

A supportive mattress should be firm enough to relieve pressure points while you sleep. If it's too soft, you risk straining your back and neck. Meanwhile, mattresses that are too firm may leave you with joint pain.

Firmness levels can be measured on a scale from 1 to 10. The lower levels are softer, while the higher ones are firmer. For more information on firmness, check out our mattress firmness guide.

The Purple mattresses are offered in both soft and firm options. Exclusive GelFlex Grid instantly adapts to your body and movements. Regardless of your sleeping position and body shape. 


Mattress Thickness FAQs

It's not easy picking the right mattress thickness. Thankfully, we're here to help! Here are some of the most common questions that shoppers have about mattress thickness.

How high do I want my bed?

Most people prefer the top of their mattress to be about 25” from the floor. At this height, you can sit on the edge of the bed with your feet on the floor. Shorter people may want a lower bed, while those who are taller may prefer more height. If you're looking for an option for couples, always go with the preferences of the shorter person.

After you choose a Purple Mattress, pick a bed frame or mattress foundation that matches your preferred bed height.

Does mattress thickness affect its firmness?

Mattress thickness is related to mattress firmness and density. In general, you can expect a softer mattress to be thicker and a firmer mattress to be thinner if they are made from the same materials.

However, the opposite is true for an air mattress since both the height and the firmness are increased by raising the pressure in the air chambers.

How do I measure mattress thickness?

Using a ruler, measure from the bottom of the mattress to the crown, which is higher than the top seam. If you have a pillow top mattress, you can lay a yardstick across the mattress with the end sticking over the edge, so it is level with the crown. Then, measure from the bottom of the mattress up to the yardstick.

To determine overall bed height, measure the height of the foundation or box spring, if you have one. If the product you want to buy is thicker than your current mattress, and you want the same overall height, then you'll need to purchase a lower bed base.

How thick is an average mattress?

The average thickness for an all-foam mattress is 9-10”. Meanwhile, the standard thickness of a hybrid model is 11 to 13”. Purple mattresses are considered to be average in thickness.

Average thickness is also specific to mattress types. For example, the average futon mattress is thin compared to most bed mattresses. The same is true for daybed mattresses, bunk bed mattresses, sofa bed mattresses, and mattresses specifically made for young children.

Inflatable guest beds are very thick compared to bed mattresses, as they are commonly designed to come close to standard bed height while sitting directly on the floor.

What is the mattress thickness rating?

  • Very thin mattresses: Under 6”
  • Thin mattresses: 6 to 8”
  • Standard mattresses: 9 to 12”
  • Thick mattresses: 12 to 15”
  • Extra thick mattresses: 16” +

Mattress thickness is only one dimension of a mattress. The horizontal dimensions for each mattress size are standardized. The full size is always 54” wide x 76” long, regardless of how thick or thin it is. Mattress thickness depends on the specific model.

How deep is a standard mattress?

For mattresses, depth and height are simply other ways to refer to the thickness of a mattress. For example, the dimensions of a full-size Purple Mattress are 54” wide by 76” long by 9.25” deep.

How much thickness is required for a mattress?

A mattress needs to be thick enough to provide both support and pressure relief at the same time. All-foam mattresses can be thinner with high-density foam in the base. Hybrid mattresses are thicker to house the wrapped coils and comfort layers.

What is a good mattress thickness?

Choosing the right mattress thickness depends on your specific needs and the type of mattress you buy. Purple has four mattresses, each with a different thickness: 9.25, 11, 12, and 13”.

The right mattress should provide you with the support and comfort you need while staying within a comfortable height. A few mattress brands have mattresses that are over 18” thick, which can be too high for most people.

Another consideration is mattress durability. As a general rule, thicker mattresses can last a little longer because they have more components to share the stress. You can also consider using a mattress protector to help your mattress last longer.

Find The Perfect Mattress Today

Before you choose a mattress, be sure to take the mattress thickness into account. Purple has four mattresses with their own thickness and design. The hybrid models are thicker than the original foam-based Purple Mattress, but each has a Purple GelFlex Grid layer in varying thicknesses.

If you're shopping for high-quality mattresses and want a great night's sleep, find the right product at Purple!