How to Determine Your Arch Height at Home

You can check your arch height at home with nothing more than wet feet and a flat surface. The simplest and most widely used self-test involves making a footprint and comparing the shape of the midfoot band to the outline of your heel and forefoot. Clinicians broadly classify feet into three categories: high arch (pes cavus), normal or neutral arch, and flat foot (pes planus), and your home footprint can place you in one of those groups with reasonable accuracy.¹ The method has limits, but it gives you a useful starting point before you ever see a specialist.

The Wet Footprint Test

This is the classic do-it-at-home method, sometimes called the “wet test.” You need a shallow pan of water, a flat hard floor, and a piece of dark-colored paper or a paper shopping bag. Wet the sole of one foot, step onto the paper with your normal standing weight, then carefully step off and look at the imprint.

What you are looking at is the contact area of your sole. The key region is the midfoot, the band connecting your heel print to the ball of your foot. A normal arch leaves a midfoot band that is roughly half the width of the forefoot. A flat foot leaves a print where the midfoot is nearly as wide as the rest of the foot, sometimes with almost no inward curve at all. A high arch produces a very narrow midfoot band, or in extreme cases, a gap where the midfoot barely touches the paper at all.

A few tips to get a cleaner result: stand naturally and don’t shift your weight forward or back. Use both feet, because asymmetry between your left and right arches is common. And do the test on a hard, level surface. Carpet or foam will distort the print.

Reading Your Footprint

Once you have a clear print, you can estimate something called the Clarke angle, which is the angle formed between the inner edge of your footprint and a line drawn across the widest part of the forefoot. A larger angle means a higher arch. In clinical settings this angle is measured with a goniometer or digitally, but even a rough visual comparison gives useful information. A recent study comparing a smartphone angle-measuring app to a standard goniometer found a very strong correlation between the two methods, with readings matching closely enough for screening purposes.² That means if you want more precision than just eyeballing your wet footprint, snapping a photo and using a free angle-measuring app on your phone is a legitimate next step.

As a rough guide for interpreting your print:

• Flat arch: The midfoot band is nearly the full width of your foot. The inner edge of the print shows little or no inward curve.
• Normal arch: The midfoot band is about half the width of the forefoot. There is a clear inward curve but the middle portion of your sole still makes solid contact.
• High arch: The midfoot band is thin, perhaps a quarter of the forefoot width or less. In very high arches you may see a nearly disconnected print where the ball of the foot and heel barely link up.

Footprint methods have been validated against imaging. One study comparing footprint-based measurements to X-ray found correlations above 90%, suggesting that the shape your foot leaves on paper reflects its underlying bony alignment quite well.³

Other Home Methods Beyond the Wet Test

The wet test is popular because it requires almost nothing, but a couple of other approaches work well at home and can confirm or refine what you see in your footprint.

The first is a simple visual check. Stand barefoot on a hard floor and have someone look at the inside of your foot from behind. If there is a visible gap between the floor and the inner sole of your foot, you have some arch. If a finger can slide under easily, your arch is moderate to high. If there is no daylight and the inner sole rests flat on the floor, you have a low or flat arch. This is crude but surprisingly consistent with what clinicians observe during a physical exam.

The second is the navicular drop test. Your navicular bone is the small bump on the inside of your foot, roughly midway between your ankle and the ball of your foot. Sit down and locate that bump. Mark its height on a card or note where it sits relative to the floor. Then stand up with your full weight on both feet and check where that bump is now. The distance it drops tells you how much your arch collapses under load. A drop of about 5 to 9 millimeters is considered normal. Significantly more than that suggests a flexible flat foot; significantly less suggests a rigid high arch.

Clinicians also use a tool called the Foot Posture Index, or FPI-6, which involves looking at six features of the loaded foot: how the heel tilts, whether bumps on the inside or outside of the ankle are symmetrical, the curve of the arch, and the spread of the forefoot. Research has found this index to be highly reliable, with inter-rater agreement scores above 0.95, meaning two different observers looking at the same foot will almost always agree on the classification.⁴ You don’t need formal training to look at most of these features. A mirror, a phone camera, and a flat surface are enough to get a reasonable impression.

What Your Arch Type Actually Tells You

Once you know your arch height, you are looking at a structural feature that affects how force travels through your foot when you walk, run, or stand. The differences are not just cosmetic. High-arched feet tend to concentrate stress in the hindfoot area, while low-arched feet spread load over a larger contact area in the midfoot.⁵ These mechanical differences also have measurable effects on balance: a study of young gymnasts found significant differences in both static and dynamic balance between those with pronated, supinated, and neutral feet.⁶

Structural differences go beyond pressure distribution. Research comparing foot types in people with diabetes found that high-arched feet had more prominent metatarsal heads, more claw and hammer toes, and different ranges of big-toe motion, while flat feet tended to show increased forefoot length and altered ankle alignment.⁷ These are features you might notice yourself if you look carefully at your toes and the shape of your forefoot.

Injury Patterns Linked to Arch Height

One of the most common reasons people want to know their arch height is concern about injury, especially if they run or play sports. The picture here is real but messier than the shoe industry would have you believe.

Flat feet have been associated with higher rates of plantar fasciitis and shin splints, while high-arched feet carry a greater risk of stress fractures and tendon problems, largely because a rigid, high arch does a poor job absorbing shock.⁸ A broad review of biomechanical risk factors for lower-limb exercise injuries confirmed that excessively high or low arches are among several structural features linked to elevated injury risk.⁹

But “linked to” does not mean “causes.” A prospective study of runners found few consistent statistical associations between arch height and specific overuse injuries, concluding that lower-extremity alignment is not a major risk factor for running injuries in recreational runners.¹⁰ The honest takeaway: arch height is one factor among many, including training load, muscle strength, and surface. Knowing your arch type gives you context, not a diagnosis.

The Shoe Matching Myth

If you have ever stood on a pressure mat in a running store and been told you need “stability shoes” for your flat feet or “cushioned shoes” for your high arches, you should know that the evidence behind that recommendation is remarkably thin. Multiple large military studies have directly tested whether prescribing shoes based on arch or plantar foot shape reduces injuries, and the answer has consistently been no.

One study of Marine Corps recruits assigned experimental groups shoes matched to their plantar shape and control groups standard-issue shoes. The result: virtually no difference in injury risk between the two groups for either men or women.¹¹ A similar trial in Army basic training found the same thing: selecting shoes based on plantar shape had little influence on injury risk, and the researchers explicitly concluded the technique was not necessary if the goal was injury prevention.¹² A meta-analysis that pooled results from three of these investigations confirmed the overall finding, showing no meaningful difference in injury rates between arch-matched and control shoe groups for men or women.¹³

This does not mean shoes don’t matter at all, or that comfort is irrelevant. It means the specific practice of choosing a shoe category based solely on your arch classification has no demonstrated injury-prevention benefit. Comfort, fit, and the type of activity you are doing are probably better guides than any arch-to-shoe matching chart.

When Orthotics and Insoles Make Sense

If shoes matched to arch type don’t prevent injuries, does anything foot-specific help? The evidence is more encouraging for custom or semi-custom insoles when you already have symptoms. A study of patients with symptomatic flat feet found that customized 3D-printed insoles performed better than prefabricated insoles at redistributing midfoot pressure and improving foot alignment over eight weeks.¹⁴ The key word there is “symptomatic.” If your flat feet or high arches cause no pain and no functional problems, there is no strong reason to buy corrective insoles.

For people who do experience discomfort, the gap between expensive custom orthotics and more affordable semi-custom options may be smaller than expected. Research comparing the two in both high- and low-arched individuals found that semi-custom devices controlled rearfoot motion nearly as well as fully custom ones, with very small differences in comfort ratings. High-arched people actually tended to find the semi-custom device slightly more comfortable in the heel and arch regions.¹⁵ If you are considering orthotics, a mid-range semi-custom option is a reasonable place to start before committing to the higher cost of a fully molded device.

Exercises That Can Change Your Arch

Your arch height is partly structural, set by bone shape and ligament length, but also partly muscular. The small intrinsic muscles on the sole of your foot actively support the arch, and strengthening them can measurably raise it. The most studied approach is the short foot exercise, where you try to shorten your foot by pulling the ball of the foot toward the heel without curling the toes. Imagine trying to dome the sole of your foot upward while keeping your toes flat on the ground.

Research confirms that short foot exercises improve arch height and reduce pain in people with flexible flat feet.¹⁶ One study comparing short foot exercises to arch support insoles found that the exercises produced significantly greater improvement in arch height (measured by navicular drop) and also improved dynamic balance more than insoles alone.¹⁷ Adding neuromuscular electrical stimulation to the exercises increased muscle size in the abductor hallucis, one of the key arch-support muscles, though navicular height changes in that trial did not reach statistical significance on their own.¹⁸

The practical upshot: if you test your arch and find it is lower than you expected, targeted exercises can improve it over weeks to months. This is especially relevant for people with flexible flat feet, where the arch exists when unloaded but collapses under body weight. A rigid flat foot, where the arch is absent regardless of load, is less responsive to exercise and more likely to need professional evaluation.

How Arches Change Over a Lifetime

If you tested your arch height years ago, the result may not hold today. Arch height is not static. It develops throughout childhood, can shift during major life events, and tends to decrease gradually with age.

All toddlers start out flat-footed. A longitudinal study that followed children from infancy found that every apparently normal toddler had flat feet at the start, and arches developed over the following years regardless of what shoes they wore.¹⁹ A large study of over 10,000 children found that the arch height ratio in boys remained relatively flat until about age 11, then rose between ages 11 and 13. In girls, a similar rise happened between ages 10 and 12.²⁰ Testing a child’s arch before their early teens may catch a foot that simply has not finished developing yet.

Pregnancy is another major event that can permanently reshape the foot. Research tracking women through their first pregnancy found lasting reductions in arch height that did not revert after delivery, with the first pregnancy appearing to have the most significant effect.²¹ The combination of weight gain and the hormone relaxin, which loosens ligaments throughout the body to prepare for childbirth, appears to stretch the structures that hold the arch up. If your shoe size went up during pregnancy and never came back down, a drop in arch height is the likely reason.

Aging brings its own gradual changes. The posterior tibial tendon, which is the primary muscular support for the arch, weakens over decades of use. Weight gain, reduced physical activity, and general ligament loosening all contribute. Retesting your arch periodically, especially if you notice new foot, knee, or hip pain, can catch changes that develop slowly enough to escape notice until symptoms appear.