PRC owner "Crazy Dave" Harkin says you should replace your running or walking shoes every 350–400 miles of use, but how do you know how many miles you've got on those shoes of yours? The PRC Shoe Wear Calculator on this page can help with that.
To use our calculator, type in the number of weeks that you've owned your current pair of running shoes, followed by your average weekly mileage during that time, and hit enter. The calculator will do the math for you and issue a recommendation. Try it for yourself!
If you received an email from us because your shoes are four months old, enter 18 weeks in the first field below.
We find that most well-made running shoes will endure 300–400 miles of use. That's not just what the shoe companies say; it's what we've learned in our 25 years in this business. Some specialized racing shoes will even expire well before you've run 300 miles in them.
When the cushioning and support in your shoes break down, that translates to wear and tear on your body. We recommend rotating a new pair of shoes into your exercise regimen when your current pair hits about 300 miles of use. Retire the old shoes when they reach 400 miles.