You’ll find plenty of instructional guides online for how to measure your feet with nothing more than a ruler, piece of paper, and pencil. However, a one-dimensional length measurement will only get you so far when Corduroy Pants & Boots.
Even if you plan to buy your shoes online, your three-dimensional foot deserves a 360-degree scan—and human interaction. To get a proper foot measurement, you have to do actual legwork and visit your local running shoe store for a fitting.
I visited Aardvark Sports Shop in Bethlehem, PA and walked through the entire shoe-fitting process myself. Every running shoe store offers slightly different methods, and not all stores may not yet operate with the newest technology. But the experience of being fitted for shoes with a foot scanner and expert know-how is similar.
Aardvark uses the Superfeet Personalized Fit Experience 3D scanner and pressure mat to provide an all-inclusive measurement of your foot. Data includes foot alignment, pressure points, ball width, arch height, and a whole bunch of other measurements in addition to just the length and width of your foot.
Some foot scanners also offer shoe recommendations. However, actually having a quick chat with a store associate is the best way to help you find a shoe catered to your personal needs and lifestyle. A store associate will ask about your running history, shoes you previously wore, past injuries, and personal preferences.
I spoke with store manager Sheena Wells about why you shouldn’t measure your feet at home. We also talked about the limitations of new shoe-sizing technology, and what you should especially pay attention to during your fitting. (It goes way beyond making sure there’s a thumbnail’s width of space between the shoe’s tip and your big toe!)
Runner’s World: Why should people not do at-home measurements to find their running shoe size?
Sheena Wells: A measurement of the foot is not just length. It also entails top-to-bottom volume (or the depth of the foot) and also the width of the foot and its shape. Some people have a little bit more of a rectangular-shaped foot. Others have more of a fan shape, or a more triangular-shaped foot.
RW: What’s the process when a runner walks into the store and has no idea what size they are or what shoe to wear?
Sheena: We now have a more advanced measuring system, which is a digital scanner. We use the old-school Brannock device less frequently. While the Brannock does measure the width across the ball of your foot, it doesn’t give you the three-dimensional aspect of that.
The digital scanner will give you a 3D imaging of your foot. There’s four cameras. You stand still on top of the scanner with your feet and ankle joints relaxed. Then, the machine captures measurements of your arch height, instep height, the width of your foot, and the length of your foot. It provides you with those measurements and also tells you how your feet stack up relative to the overall female or male population.
RW: From what your staff has experienced, how common is it that one foot is a different size from the other?
Sheena: Very common. It’s actually abnormal to have exactly symmetrical feet. It’s more of an oddity if your feet are the exact same size. Still, the difference between the size of each foot is probably not that big. That is, you should go by your bigger foot size.
RW: Besides going a half size up after using the larger foot’s scan size, how else do you determine what shoes a runner should wear?
Sheena: I like to think of the Brannock or the 3D-fit station as a starting point. From there, we check for several things from the exterior view to see if you have a proper fit.
For example, you want a thumbnail’s width of dead space between your longest toe and the end of the shoe. We assess this when you are standing with your full weight evenly distributed on both feet. You’ll be looking straight ahead and letting your feet relax inside the shoe. We also look to see if we can grab a little bit of material across the top of the shoe’s upper.
You want parallel lacing. If there’s a deep “V” Een, this can indicate that the shoe is not wide enough or that the runner requires more depth in their shoe. We ask questions like, “Is there a lot stress on the material throughout the upper mesh? Is there buckling or puckering of material?” If so, this can tell us if shoe’s too wide or too narrow.
RW: What are some other strategies you use to determine a runner’s correct shoe size?
Sheena: We put the shoe on the runner’s foot and tie it ourselves. This lets us see if the runner has any hesitation or resistance to their foot entering the shoe. That’s an indication right off the bat that the shoe is probably a little bit snug.
Of course, after we assess those things from the outside, we’ll always ask the runner how the shoe feels. I always ask, “Do you feel any constriction? Can you move your toes? Would you be able to play the piano with your toes in your shoes?” You want the space because your foot needs to be able to move inside the shoe to absorb impact properly and remain strong. If we inhibit motion, your foot and toes can become weak and atrophied.
RW: What’s the difference between men’s and women’s shoe sizing?
Sheena: It is a size and a half difference. For example, a men’s size 7 equates to a women’s size 8.5. And then, a men’s regular width is equivalent to a women’s wide width. A women’s regular width is equivalent to a men’s narrow width.
For instance, if a woman needs an extra-wide shoe, I can give her this option. Assuming her foot is long enough for a men’s size, I can bring out a men’s wide shoe, which is equivalent to a women’s extra wide. This allows us to have a little bit of Shorts room for those less-typical types of sizing.
Amanda is a test editor at Runner’s World who has run the Boston Marathon every year since 2013; she's a former professional baker with a master’s in gastronomy and she carb-loads on snickerdoodles.
