Benjamin Ring gives a brief explanation of the American system for rating climbs. A Los Angeles law enforcement officer, Benjamin Ring enjoys recreational rock climbing in places like Malibu Creek.
The Yosemite Decimal System is a systematic yet relative way of classifying the difficulty of hiking and climbing terrain. The fifth and hardest class is further divided into decimal points to create a more descriptive breakdown of the technical difficulty of hard climbs. A climb or trail is always rated based on its hardest part, even if it is a very short section.
Hiking or walking along a fairly well established trail for an hour or two.
A cross-country trail that requires route finding skills and some travel through talus or thick brush. Less than half a day required.
Scrambling over rocks and the use of hands for balance, though it has less exposure than fourth or fifth class and does not require technical climbing skills. Average of half a day to climb.
Steep terrain that requires using rope belay, but not placing protection. Climb could take a full day.
Technical climbing where a rope, climbing hardware, and safety skills are required. A fall would likely mean serious injury or death. Climb takes two days.
The fifth class is further broken into a decimal system ranging from 5.0 to 5.15. When the rating reaches 5.10, the ratings are further divided with a letter grade from a-d (5.10a, 5.10b, etc.).