Depending on the brand, a pair of jeans marked “size 29” usually fits like a U.S. size 8 or 10. The 29 means that the waist size is 29 inches, but even this measurement isn’t always right.
Different brands have very different sizing standards, so a size 6 from one brand might fit like a size 10 from another. Some brands also use “vanity sizing,” which is when smaller sizes have bigger measurements so that customers think they can wear smaller sizes than they actually can. The best way to make sure jeans fit well is to try them on before buying them. If you’re buying jeans online, you can use a size chart to find the right size based on your waist size and the length of the inseam.