What Mattress Thickness Should I Buy?

Written by
Purple Staff
Last Updated
April 5, 2022
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

Mattress Thickness Purple

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



The Purple Mattress


Purple Plus Mattress


Purple Hybrid


Purple Hybrid Premier with 3” Purple GelFlex Grid


Purple Hybrid Premier with 4” Purple GelFlex Grid


As a general rule for mattresses made out of 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.

Purple Mattresses By Thickness Levels

Purple has four mattress models, each with a different height. The original Purple Mattress has a supportive foam base, while the three hybrid mattresses have wrapped coil bases. Here's an in-depth look at each model:

The Purple Mattress (9.25”)

Thickness: 9.25”

Special features:

  • 2” foam-encased Purple GelFlex Grid comfort layer
  • Encasement for edge support

Transition layer: 3.5” high-density polyurethane foam (1.8 lbs.)

Base layer: 4” layer of polyurethane foam (2.0 lbs.)

Firmness: Medium to medium-firm

The Purple Mattress is the product that put us on the map. Despite being one of our thinner mattresses, it features unbeatable comfort and flexibility. The transition layer also adds support beneath the polymer grid.

This type of mattress is suitable for all sleeping positions, including side sleepers and combination sleepers. The 2” of GelFlex Grid layer relieves pressure points and prevents shoulder or hip pain.

Apart from being a popular choice for petite and average-sized adults, this 9” mattress is also suitable for young people. The twin size is recommended for children, while the twin XL and full sizes are great for older children and teenagers. It is not recommended for persons weighing over 250 pounds.

Purple Plus Mattress (11”)

Thickness: 11”

Special features:

  • Foam-encased 2” Purple GelFlex Grid comfort layer
  • 2” layer of Premium Comfort Foam underneath
  • Foam case around the grid for edge support

Base: Two layers of Purple's original polyurethane foam

Firmness: Medium to medium-firm

The Purple Plus Mattress is the upgraded version of our signature Purple Mattress. Thanks to an extra layer of premium foam, this model provides better pressure relief, cushioning, responsiveness, and breathability.

Aside from the foam base, the mattress is topped with a 2” of ​GelFlex Grid to relieve pressure points (like the hips and shoulders) while keeping the rest of your body fully aligned for amazing sleep.

Purple Hybrid (11”)

Thickness: 11”

Special features:

  • Foam-wrapped 2” Purple GelFlex Grid
  • Supported by strong wrapped coils

Firmness: Medium-firm

The Purple Hybrid is recommended for back sleepers and stomach sleepers, but it can work for most sleep positions. Whether you're a side or combination sleeper, you can have a relaxing sleep on this mattress.

This product is an excellent choice for average-sized people. The individually wrapped coils also make this model and the Hybrid Premier mattresses work well for bigger and taller sleepers since they provide more support. In general, this model works well for older children and teenagers.

Purple Hybrid Premier with 3” Purple Grid (12”)

Height: 12”

Special features:

  • Purple GelFlex comfort layer

Firmness: Less firm than Purple Hybrid

At 12” high, the Purple Hybrid Premier with 3” Purple GelFlex Grid is suitable for everyone. With a 50% higher grid, it is less firm than the Purple Hybrid.

The Purple Hybrid Premier with 3” Purple GelFlex Grid provides comfort and support for all types of sleepers. It is recommended for larger adults and heavier people because of the support of the coils, while also accommodating petite persons because the higher grid makes it more pliable. This is a great choice for couples who have different firmness preferences.

Purple Hybrid Premier With 4” Purple Grid (13”)

Thickness: 13”

Special features:

  • 4” Purple GelFlex comfort layer

Firmness: Soft

Purple Hybrid Premier with 4” Purple GelFlex Grid is the tallest and softest Purple mattress. It sets itself apart from other hybrid models by having an extra 4” thick Purple GelFlex Grid layer.

The Purple Hybrid Premier with 4” Purple GelFlex Grid is suitable for all sleeping positions, including back and stomach sleepers, thanks to the responsive wrapped coil support. Plus, due to its pliability, the 4” Purple GelFlex Grid is suitable for people over 250 lbs. Whether you're a taller sleeper or someone who simply enjoys sleeping on a soft mattress, this model is great for you.

Lady On Purple Hybrid Partial

Purple Hybrid

Our most firm mattress. More firm while not sacrificing comfort.

Purple Hybrid 3 Partial

Purple Hybrid Premier 3

Our best seller. The ideal balance of softness and support.

Purple Premier 4 Partial

Purple Hybrid Premier 4

Our most plush and premium mattress. Providing premium comfort without sacrificing the support you need.

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”
  • Very thick mattresses: 15 to 20”
  • Extremely thick mattresses: 20” and up

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!