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The Brannock Device

Peter C

Back to How-To

When was the last time you had your foot measured?  I’ve spent many hours on retail floors across the country and when I ask that question, customers often reply, “not since I was a kid.” A lot can change from the time you were 15.  Believe me, at 60, I sure have had that experience.  Age, weight, birthing a child, (no, I didn’t do that), knee or back injuries (yes, I’ve had that) and all sorts of things can change your foot size and shape over time.  So, if you haven’t been measured since you were 15, it’s high time you get yourself to a good sit and fit shop and as for someone to use a Brannock device on your feet.

The Brannock device is a tool that was patented by Charles Brannock in 1927 and it is the most accurate tool (96%) in correctly measuring your feet. I’ve heard store employees and customers say things like, “That’s such an old tool and it hasn’t changed. It can’t be that accurate.” I like to remind them that a ruler is an old tool that hasn’t changed either and I know it’s not version 15.7 of an app on your phone, but it still works just fine. 

A Brannock device measures three important features of your foot: Length, Width, and Arch Length.  The first two are obvious, but the latter may be something many people do not quiet understand.  It is important to have a shoe that is long and wide enough, but does it flex in the right spot given the shape of your foot?  This is where arch length matters.  Your arch length is the distance from your heel to the bump on the joint (the metatarsal head) of your big toe.  It is where your foot flexes when you take a step.  Ideally, you want to have that part of your foot line up with the part of the shoe that flexes when you walk. Most people do not pay much attention to this measurement.  They will wear a shoe that their foot fits into, but sometimes they find they are getting heel lift, blisters, discomfort, or worse, pain from things like plantar fasciitis.  Taking note of the arch length will go a long way to avoiding such maladies. In fact, arch length is probably the most important measurement when choosing the proper shoe.

Take for example the photo of Kelly’s foot. Reading the pink bars (women), her foot length is exactly 7.5.  Her width is between a B and a C and her arch length is 8.5.  Where she will physically fit into a 7.5 shoe, she will better fit into a size 8.  A general rule is to split the difference as a good starting point to begin trying on shoes.  If I were the employee on the floor, I’d bring out 8’s and 8.5’s for Kelly to try.  Remember a good fit leaves plenty of room for the toes so there is no contact with front, top or sides of the shoe.  The heel is comfortably in place with no heel lift or forward motion and there is no sloppy side to side motion. 

Now let’s look at Iain’s foot. His left foot measures (read the blue) 10.5 Length, C/D width, and about 12 on arch length.  His right foot is a little over 11 length, C/D width and 12.5 arch length.  Again, where he would fit into a size 11 shoe, he fits much better into a 12.  His foot stays in place with the Oboz O FIT insole, it flexes in the proper spot and it is comfortable. 

For more on this, check this video on our website.





Peter C

Peter is an Outreach & Training Specialist with Oboz. 

More about Peter? Here you go: 

  • He likes Bryce National Park so much his kid is named after it; he highly recommends a visit if you can
  • As a teacher he took students all over the country hiking; now he gets to travel all over and teach about hiking footwear
  • Loves to connect people to the outdoors; just ask and he’ll try to help you

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