Everything You Need to Know About Coil Gauge, Count, and Types

Written by: Katarina Pucijasevic
Updated: 05/22/2024

A good mattress needs to give you the right level of comfort and support, and that happens with the help of different mattress materials. 

One of those materials is about giving you sturdy support and some bounce. Those are coils. 

This guide will cover everything you need to know about mattress coils – what they are, the different types, the coil gauge and coil count, and more. 

Let’s get into it and find out what makes your coil mattress so comfortable. 

What Are Mattress Coils?

Coils are sturdy metal springs used in the support core of hybrid and innerspring mattresses.

Most mattress coils are made from tempered steel. The tempering process makes the material more durable by repeatedly heating or cooling it. 

Coils can provide more firm support because they are made to bend under stress but spring back when the pressure is removed. Their support core structure improves airflow and doesn’t trap body heat, making coil mattresses ideal for hot sleepers. 

Coils’ support, comfort, and durability depend on coil types, counts, and gauges. Also, there are some coils that aren’t used in the support layers but in the comfort layer. 

So, if you’re looking for a coil mattress, you should know that not all of them are the same. 

What Is the Purpose of Mattress Coils?

Mattress coils are crucial in supporting your body and ensuring even weight distribution. They stabilize the mattress and keep your spine aligned. 

Their position in the mattress’s support layer provides deep spinal support, and the comfort layers on top cushion and relieve pressure. 

Coils contract and expand under pressure, so they feel buoyant and easy to move on. They also tend to have excellent edge support and durability. 

The firm support of the steel coils can make them an excellent choice for heavy-weight sleepers. 

Mattress Coil Count

The mattress coil count refers to the total number of coils in a mattress, which can significantly influence its performance. 

The coil count can also vary greatly with a specific mattress size. For example, a Queen mattress can have a coil count between 400 and 1,200. 

Avoid a coil count below 400 for Queen coil mattresses. On the other hand, a Twin or Full size mattress should have a coil count of around 300. 

Also, coil type affects coil count. Because Bonnell and offset coils are larger, they have lower coil counts than support cores with smaller, pocketed coils. 

Although a higher coil count is desirable, it doesn’t necessarily mean that a lower coil count is worse. Types of mattress coils, coil gauges, height, shape, and metal quality affect mattress firmness and durability. 

Mattress Coils Gauge

Coil gauge refers to the thickness of the coils and is another significant factor in mattress performance. 

Coil gauges range from 12 to 17, with lower gauges indicating support and higher gauges indicating flexibility. Standard mattress gauges are between 13 and 17. 

The seller should have all of the information about the coil gauge of your mattress. And if they don’t know the gauge for whatever reason, you can contact the mattress manufacturer to provide you with the correct information. 

If you like a firmer mattress, choose a lower gauge. On the other hand, high gauge coils make a softer mattress. However, most prefer a gauge between 13 and 15 for comfort and durability. 

Mattress Coil Types

There are several types of mattress coils, such as Bonnell, offset, continuous, and pocketed coils. They all differ in some way, but we’ll help you learn the characteristics of each so you can find the perfect mattress. 

Bonnell Coils

Bonnell coils are also known as hourglass coils because of their distinct shape. This shape makes a comfortable mattress because the thinner middle portion flexes under minimal pressure, and the thicker end provides ample support. 

Bonnell coils move together and provide even support throughout the mattress thanks to helical wires. However, this design makes adjusting to different weights and sleeping positions harder. 

Initially the go-to for an innerspring mattress, Bonnell coils are budget-friendly with reliable edge support. But they may become noisy over time and have no motion isolation. 

While they may not be ideal for daily use by adults, they make a good mattress for kids because they don’t weigh as much, or in guest bedrooms, which aren’t used often. 

Offset Coils

Offset coils are like a more refined version of Bonnell coils. They are hourglass-shaped and connected with helical wires, but offset coils have squared top and bottom sides. 

This design reduces noise and motion transfer and makes the mattress more responsive and comfortable. The coils flex under pressure and provide robust support even under heavier weight. Offset coils come in various configurations, such as those with hinges on both sides. They’re more expensive to manufacture than Bonnell coils, so they cost more, but the benefits make them a worthy investment. This shape is often used for innerspring coils.

Continuous Coils

A single wire is bent into rows of loose coils and connected by helical wires to create continuous coils.

The connecting wires ensure even spacing between the coils, minimizing motion transfer, but they can still transmit some movement. 

Continuous wire coils are stable but not as quiet or contouring as offset coils. Ideal for mattresses with thick comfort layers like memory foam or latex, they are affordable and quick to make. 

If you’re looking for an affordable mattress without compromising durability, look for one with continuous wire coils. 

Pocketed Coils

Pocketed or Marshall coils feature multiple smaller coils individually wrapped in fabric sleeves. 

Each of the individually wrapped coils moves independently within its casing, allowing the mattress to conform to the body. Also, unlike Bonnell and offset coils, pocket coils have a cylindrical shape that helps them distribute pressure evenly. 

The fabric sleeves are sewn or glued together, preventing motion transfer between the cylindrical springs. This makes a pocketed coil mattress an excellent choice for couples

While their intricate construction may come at a higher price, pocketed coils offer increased durability, support, and noise reduction.

Micorcoils, Minicoils and Nanocoils

Microcoils, nanocoils, and minicoils are often featured in the comfort or transitional layers of mattresses, adding responsiveness, durability, and support. 

Ranging from 1 to 3 inches in height, these smaller springs, individually wrapped for better contouring, create balanced pressure relief. 

Found in hybrid mattresses, these coils enhance airflow in the comfort layers and reduce heat retention. Mattresses with mirco, nano and minicoils are an excellent choice for hot sleepers who need more comfort. 

Mattress Coils: Pros and Cons

Mattresses with coils can make great cooling mattresses, but their construction also makes them prone to transferring motion, so couples might not like it. So are coils worth it? Let’s weigh in. 


  • Coils are made from temperate steel, so they’re very durable.
  • Their business gives you a responsive feeling during sleep.
  • The coils offer firm support.


  • Coils that are too old can cause back pain because they become less supportive..
  • Coils might produce squeaking sounds as the mattress ages.
  • Some mattress coil types transfer motion.

Mattress Types With Coils

Two different mattress types feature a coil layer. Here’s what you need to know about them. 

Innerspring Mattresses

Innerspring mattresses use a coil support system, typically made of tempered steel. The coils in an innerspring mattress offer a supportive and responsive feel, ideal for those who prefer a bit of bounce with great breathability. You can find an innerspring mattress in various designs and price ranges.

Hybrid Mattresses

Hybrid mattresses combine the coil support of an innerspring mattress with the comfort of all-foam mattresses. It’s like getting the best of both worlds—supportive bounce and cozy contouring. They often use pocket springs, making them better at motion isolation. A hybrid mattress provides great sleep quality for all body types and sleep positions.

Frequently Asked Questions

How Many Coils Should a Mattress Have?

The ideal number of coils for a mattress varies by size. For a Twin or Full, aim for around 300 coils, while a Queen should have at least 400. If you’re living large with a King, shoot for 480 coils. California King? Go big with around 800 coils for maximum comfort.

What Is a Good Coil Gauge for a Mattress?

The optimal coil gauge is based on personal preferences and sleeping habits, balancing the right amount of support and comfort. Lower gauges (thicker coils) mean firmer, more durable support, while higher gauges offer a softer feel. For a balanced choice, consider 13 to 15.

Are Coil Mattresses Bad for You?

Coil mattresses are not unhealthy—their quality matters, with benefits like durability and airflow. A well-maintained coil mattress can provide excellent support, comfort, and relieve pressure points.

Can You Flip or Rotate a Coil Mattress?

Yes, rotating your mattress extends its life. However, most modern coil mattresses aren’t designed to be flipped. Check your mattress care instructions to see if it can be flipped. Not following these instructions could void your mattress warranty.

Final Thoughts

Now you know everything about the different coil types and how they work, and you’re ready to buy a new spring mattress!

Remember, it’s not just about the number of coils or the coil gauge; it’s about finding the right level of support and comfort your body needs. Your spine should be aligned no matter how you sleep and have ample pressure relief. 

We wish you a good night’s sleep!

Reviews written by:

Katarina Pucijasevic - Junior author

Katarina is an Author at Anatomy of Sleep, full of fresh ideas and the drive to tackle things.
With real sleep issues during her studies, Kat had dug deep to figure out what was causing her irregular sleeping schedule, and it turned out a wrong, worn-out mattress topper was the culprit.
Thankfully today, she has no sleeping problem but does a lot of copywriting, proofreading, and content optimization on the theme of mattresses, sleeping products, and ways to sleep in the healthiest way possible.
She loves immersing herself in gothic fiction when not analyzing mattresses.

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