Gravel and cyclo-cross tires

35–40 mm: faster riding, mixed terrain (asphalt, gravel)
40–45 mm: a universal compromise for comfort and grip
45–50 mm: more technical terrain, more comfort, more traction

When choosing the right tires, the inner diameter of the tire and its width are important. The inner diameter of gravel and cyclo-cross tires is most often 700 mm (28 inches). You can pick from tires and tubes, which are available in different widths and with different tread patterns. With wider ones, you may be limited by the width of the rim or the space in the bike frame, so check the recommendations of your component manufacturers. For some products, you will find the TPI (threads per inch) number. The higher the number, the lighter the tire and the lower rolling resistance, but it is also less durable. Tires may be suitable for tubeless use, this information is listed with the product. To install the tube, you will need a special glue or double-sided adhesive tape designed for this use.

What is the difference between a gravel tire and a cyclo-cross tire?

Cyclo-cross (CX) tires are typically narrower (33 mm max) due to racing rules, designed for short, intense rides in mud and grass.
Gravel tires are wider (35–50 mm), designed for long rides, gravel, forest roads and asphalt. They offer more comfort and stability.