Shoe Stack Height Explained: What It Is and Why It Matters

What is stack height?

Stack height refers to the vertical thickness of the sole between your foot and the ground. It is typically measured from the outsole to the insole, not including the removable insole if one is present. This measurement is expressed in millimeters and appears on many shoe specification sheets.

The stack height matters because it decides how much material, usually foam or other cushioning, is located under your foot. A larger stack height generally means more cushioning and a softer landing, while a smaller stack height places your foot closer to the ground and gives you a firmer, more direct feel.

Your foot and ankle are complex structures, and footwear that supports them properly is important. The American Podiatric Medical Association stresses that your feet are your foundation for a healthy and active life. Choosing the right stack height is part of that support.

How is stack height measured?

To measure stack height, start at the bottom of the outsole and measure straight up to the surface on which your foot rests, which is the insole or footbed. If a shoe has a removable insole, the measurement is taken to the top of the midsole layer below that insole, because removable insoles change the number and are not always present.

Manufacturers may also report stack height with or without the insole, so comparing shoes from different brands requires you to check whether the number includes the insole. Most reputable spec sheets state the method.

Stack height is not the same as heel height. Heel height refers to the difference between the heel and forefoot, while stack height is the absolute thickness under a specific part of the foot. For a detailed look at heel height, see our heel height measurement guide.

• Measure from the outsole to the insole, excluding any removable insole.
• Use a ruler or caliper for accuracy, though many manufacturers list the spec.
• If the number is not listed, you can approximate by measuring the sole thickness at the heel.

Low stack shoes: ground feel and stability

Low stack shoes typically have a thinner sole, often below the mid-range. They offer a low-to-the-ground feel that many wearers describe as natural and responsive. Because there is less material between your foot and the surface, you have better proprioception, which is your awareness of the ground beneath you.

This ground feel can improve balance and stability, especially on uneven terrain. Low stack shoes tend to be lighter and more flexible, making them a good choice for casual wear, driving, or walking on flat indoor surfaces. They are also popular for people who prefer a minimalist experience or who have strong feet and want less interference.

The downside is less cushioning. Without sufficient foam, your feet and joints absorb more impact with every step. This can be uncomfortable for people who spend long hours on hard floors or who have conditions like plantar fasciitis. The American Academy of Orthopaedic Surgeons notes that conditions affecting the foot and ankle are common, so choosing appropriate footwear is part of prevention.

Medium stack shoes: the balanced middle

Medium stack shoes are the most common for everyday wear. They provide a moderate amount of cushioning that softens impacts without lifting your foot too far from the ground. This balance makes them versatile for walking, standing, and light errands.

Most lifestyle and casual shoes fall into this category. A medium stack helps absorb the shock of walking on pavement while still allowing enough ground feedback to keep your stride stable. For people with average arch support needs, a medium stack is often a safe starting point.

If you are unsure what you need, our shoe cushioning soft vs firm guide explains how to decide based on comfort preference. Medium stack shoes also pair well with different types of insole materials, so you can fine-tune the feel.

High stack shoes: maximum cushioning

High stack shoes place your foot further from the ground, often in a thick layer of foam or other cushioning. These shoes are designed to absorb significant impact and provide plush comfort, making them popular for long standing jobs, running, or recovery days.

The extra height can reduce pressure on the heels and knees, which is helpful for people with joint pain. However, a high stack also raises your center of gravity and can make the shoe less stable, especially on uneven surfaces or during quick lateral movements. The sole is wider in many high stack models to compensate, but the tradeoff between cushioning and stability remains.

The midsole foam is the key component in high stack shoes. Our midsole foam comparison explains how different materials change the ride. If you spend most of the day on your feet, a high stack work shoe might be beneficial, but you should also pay attention to the shoe's sole hardness and tread pattern.

Stack height vs. heel drop

Stack height and heel drop are two different measurements that are often confused. Heel drop is the difference between the height under the heel and the height under the forefoot, also called offset. A shoe with a 0 mm drop is flat, while a shoe with a 10 mm drop is more elevated at the heel.

A shoe can have a high stack height and a low drop, such as a maximal cushioning shoe that is flat under both heel and forefoot. Conversely, a low stack shoe can still have a high drop if the heel is much thicker than the forefoot.

To understand how drop affects your gait, read our heel drop guide. When choosing a shoe, consider both numbers, not just one. The stack height gives you a sense of ground height, while the drop tells you about the angle of your foot.

How to choose the right stack height

Start by thinking about your primary use. If you are on your feet all day on hard surfaces, a medium to high stack will reduce fatigue. If you prefer a firm, connected feel and have good foot health, a low stack may be enough.

Your body weight also plays a role. Heavier individuals often benefit from more cushioning to disperse force, but they also need sufficient stability to avoid rolling an ankle. Try on different options and walk around, focusing on how your feet feel after a few minutes.

For general guidance, browse our buying guides by style: for balanced choices, see best men's shoes or best women's shoes. For work environments, best work shoes and best work boots list models across stack heights. And if you prefer a casual look, best slip-on shoes covers many low to medium stack options.

What to pick for your use

Questions

Does a higher stack height always mean more cushioning?

Generally yes, because a thicker sole provides more space for foam or other cushioning materials. However, the density of that material matters too. A thick layer of firm foam will feel different than a thin layer of soft foam.

Is a high stack height unsafe for my ankles?

High stack shoes put your foot further from the ground, which can reduce ankle support and increase the risk of rolling if you step unevenly. Many high stack shoes have a wider sole to add stability, but if you have weak ankles, a lower stack may be safer.

How do I measure stack height on my own shoes?

Remove the insole if it is removable, then place a ruler against the side of the shoe. Measure from the ground to the top surface of the midsole under where your foot sits. If you measure with the insole in place, note that the number will be slightly higher.

Does stack height affect the fit of a shoe?

It can affect how the shoe feels during walking, especially the amount of flexibility and the bend point. A higher stack often means a stiffer sole, which may require a longer break-in. It does not usually change the length or width fit, but it can alter how the shoe fits around the ankle.