What is Stack Height?

From barefoot to maximal and everything in between, a running shoe's stack height plays a huge factor in how it feels underfoot. Read on to learn what stack height is, how it affects runners, and exactly how we measure it at Running Warehouse.

Stack height is the term used to refer to the amount of shoe material between your foot and the ground. Stack heights can range from barefoot to maximal, and this measurement is often equated with the amount of “cushioning” that a shoe has. A shoe with more cushioning will have a higher stack height while a shoe with less cushioning will have a lower stack height. Although shoe foams and materials differ greatly and a shoe’s stack height is not always equivalent to whether it feels soft or firm, it is a great place to start when considering the right shoe for your running needs.

Combined with a shoe's offset and the level of softness from the foam, stack height plays a big part in how cushioned and protective a running shoe feels underfoot. Those looking for more ground feel should generally look for shoes with a lower stack height, while those who want a maximum level of cushioning and protection should choose a shoe with a higher stack height.

Heel to toe drop is another factor to take into account when considering a shoe's level of cushioning. Heel to toe drop is a measurement of the difference in cushioning between the heel and the forefoot. This matters because higher heel-toe drops tend to favor heel-strikers while lower drops cater towards mid to forefoot strikers. For more in-depth information, check out our article on heel-toe drop and how it can affect your running experience.

There are several different ways to measure a shoe's stack height, and no one standard exists. In order to simplify the process of finding if a shoe is compliant with the World Athletics stack height regulations (cannot exceed 25mm for track events of 800m and above or 40mm for road events), we have changed the way we measure shoe stack heights to now include the sock liner. Here's how we take the measurements at Running Warehouse:

Heel Stack Measurement:

Using a special device, we measure the distance from the bottom of the outsole lugs to the top of the shoe’s insole. This measurement is taken from the center of the heel while the shoe is sitting flat on a level surface. This initial measurement is the heel stack height provided on our product pages.

Forefoot Stack Measurement:

Once the heel is measured, we subtract the brand’s stated heel-toe offset for the shoe. This new measurement is the forefoot stack height. Midfoot and forefoot strikers should pay better attention to this measurement because it is more relevant to how much cushioning will be underfoot on their landings.

Minimal and low stack height running shoes offer little cushioning, with some "barefoot" shoes having the least amount of midsole material. Because of the minimal amount of cushioning, shoes with low stack heights are appreciated by runners who prefer a more natural running experience. People who enjoy running in shoes with a low stack height would rather feel the ground than the cushioning. The thought process is that since there's not much cushioning to absorb impact, your body will adopt a more natural gait, strengthen foot and leg muscles, and become better at minimizing impact and injury.

• Value a more natural running experience
• Prefer feeling the ground over the cushioning of a shoe
• Would rather let their body adjust to minimize impact than rely on the shoe to absorb impact

The majority of runners prefer shoes with a stack height that falls near the middle of the spectrum. This is because shoes with a medium amount of cushioning tend to be versatile enough for pretty much every type of run or distance. If you are new to running or are looking for one shoe that can do it all, we recommend starting with a shoe that has a medium stack height.

• Value versatility
• Want a single shoe that will work for every run
• Prefer a shoe with a balance between cushioning and responsiveness

At the other end of the spectrum, highly cushioned and maximalist running shoes provide a ton of cushioning underfoot. This thick padding produces a high level of protection from the impact of running. People who prefer running in shoes with either high or maximal stack heights, enjoy a plush running experience with the highest level of impact protection available.

• Value a comfortable, protective running experience
• Prefer feeling the cushioning of a shoe over feeling the ground
• Would rather their shoe absorb impact than their body