The Yosemite Decimal System (YDS) is used in the United States to determine the risk, difficulty, and commitment associated with rock climbing. Let’s break down this system to better understand what it all means!
Class
Class describes a climb or an approach/descent to or from a climb. Class indicates the general level of risk associated with that terrain.
- 1st Class can be described as simply a hike or walk. 1st Class terrain does not require the use of hands for navigation.
- 2nd Class is a hike with some steep inclines or scrambling, where you may occasionally want to use your hands. Generally, there is little risk of a fall, and you can expect this terrain to be what many would consider a “normal hike” in the mountains.
- 3rd Class is where we start to see a change from what we might consider “normal.” 3rd Class terrain can be defined as a hike with scrambling and some exposure. There may occasionally be a risk of fall, but often, there is no need to be clipped in. Many folks want to consider protecting some sections of third-class terrain with a rope or handling.
- 4th Class is where it gets a little more real! 4th Class is a scramble requiring the use of hands, with high exposure and fall potential. A rope is used to prevent a serious long fall that could result in injury or fatality. In 4th Class terrain, it can be easy to forget the seriousness of the position because it’s not difficult terrain to navigate, typically just high.
- 5th Class is rock climbing as we know it, defined by technical rock climbing terrain requiring a rope and belay. There is a high risk of injury or fatality from a long fall when navigating 5th Class terrain without the use of a rope.
Ratings
5th Class climbing is further broken down into subcategories indicating difficulty and additional risk ratings. These are the ratings you’ll see on the rope wall at your gym.
Generally speaking, we break down 5th Class into a scale ranging from 5.0 to 5.15. These ratings are read as “five-seven” or “five-ten” rather than “five-point seven” or “five-point ten.”
A note: While these are technically called ratings, climbers often conversationally refer to these numbers as the “grade” of a climb. For more info on common climbing phrases, check out our Glossary!
Letter Grades
Once we reach 5.10, ratings are broken down further, using a letter system to indicate additional difficulty—for example, 5.11a or 5.13c. The system uses the letters a, b, c, and d to indicate the increase in difficulty between number ratings.
Additionally, two other letters can be used to indicate serious risk. You might see R, R/X, or X:
- The letter R means runout! Runout means there is a lot of climbing or distance between protection (bolts or trad gear), so it’s essential to be aware of the chance of a fall and injury.
- The letter X indicates no or very minimal protection, making the climb much more risky.
Here are some examples of how these ratings are written:
- 5.7
- 5.10a
- 5.13c R
Grades
Finally, let’s talk about Grades. We often conversationally refer to climbing ratings and grades synonymously, but there is a more specific definition for a grade in climbing. Grade is the term and system we use to indicate the commitment it takes to do a particular route.
- Grade I is low commitment, typically just a few hours of climbing.
- Grade II is the next step up, referring to a multi-pitch climb generally in the 2-4 pitch category with an easy approach/descent and straightforward climbing. Usually, a 2-4 hour commitment on the rock.
- Grade III is similar to grade II but a little bit bigger. Ranging from 4-6 hours, less straightforward route finding or more difficult climbing but still in the category of straightforward approaches/descents.
- Grade IV is a full-day adventure. Usually in the 8-10 hour range with long approaches, committing climbing, and or 4th class descents. Grade IV is easy to underestimate, and you may find yourself strolling back to camp or the car after dark if things take more time than anticipated! To be prepared for these circumstances, bringing a headlamp in your pack is always a good idea!
- Grade V is an overnight adventure. This is some serious climbing, requiring two days to compete. In Grade V and Grade VI, climbers set up a portaledge to sleep on the route overnight.
- Grade VI is a multi-day adventure. These climbs take more than two days to complete, all while hanging out on some big ole rock!
On the East Coast, the terrain is rarely more than Grade IV when it comes to the height of our rock climbs. However, we make up for it in difficulty and commitment in certain locations like the North Side of Looking Glass Rock or Whitesides Mountain.