I need new tires and not sure what size to order. Here are photos of my bike tires. I see 622x 15, but also see 25mm as a stand alone number. 622-25 seems more likely for my road bike, not sure if the 15 is correct. Any help would be appreciated.
15 is the inside width of the rim in millimeters. The tire should be wider than that so that is stays on the rim. 19 to 28 mm in the second picture sounds like a realistic range of suitable tire widths for this rim, but in practice people have used 35mm cyclocross tires on rims like this without problems.