As a general rule of thumb, shoes can last for an average of 500 miles. If you haven’t been clocking your miles, Mendeszoon recommends a “taco test” for telling if it’s time. “This is when you take off your shoe and fold it and, if it folds in half very easily and doesn’t spring back, that means the shoe has passed its prime,” he said. Another way is to check if the traction on the bottom is worn down to the midsole. If so, it’s time for a new pair.