What Is the Yosemite Decimal System?
The Yosemite Decimal System (YDS) is the primary climbing grading system used in the United States and Canada. It is also widely understood internationally, especially among climbers who travel to North American destinations like Yosemite Valley, Red Rock Canyon, Joshua Tree, and Smith Rock.
The system divides outdoor terrain into five classes based on the type of movement required:
- Class 1 — Walking on a trail
- Class 2 — Simple off-trail hiking, some scrambling
- Class 3 — Scrambling; hands needed, significant fall risk
- Class 4 — Steep scrambling; a rope is sometimes used
- Class 5 — Technical rock climbing; a rope and protection are standard
All technical rock climbing falls under Class 5, and the decimal subdivisions (5.0, 5.1 ... 5.9, 5.10, 5.11 ...) describe how hard it is. When climbers talk about "YDS grades" they almost always mean these Class 5 ratings.
The Letter Subdivision (a, b, c, d)
Up through 5.9, a single number is enough. But from 5.10 onward, the difficulty range within each number became too wide to ignore. Letter suffixes — a (easiest), b, c, d (hardest) — were added to provide more granularity. So the scale from 5.10 onward runs: 5.10a, 5.10b, 5.10c, 5.10d, 5.11a, 5.11b, ... 5.15d.
Some climbing areas (particularly in the southeastern US) use the old-school notation "5.10-", "5.10", "5.10+" for easy/mid/hard 5.10 instead of the a–d subdivisions. Both notations are still in use, though a–d is dominant.
Origins and History
The YDS was developed by the Sierra Club in the 1950s, building on earlier work by rock pioneer Francis Farquhar. It was initially a simple decimal system, but as climbers in Yosemite — notably Royal Robbins, Warren Harding, and Yvon Chouinard — pushed the limits of what was possible, the need for a more detailed upper end became clear.
The 5.10 grade was once considered at the absolute frontier of human ability. By the 1980s, sport climbing had driven grades past 5.12. Jerry Moffatt and Patrick Edlinger established some of the first 5.13s in the early 80s. The 5.14 barrier was broken by Wolfgang Güllich on "Action Directe" (proposed as 5.14d/9a) in 1991. Today 5.15d (Font 9c) is the acknowledged frontier.
Complete YDS Grade Table with Equivalents
| YDS Grade | Fontainebleau | UIAA | Australian | Level |
|---|---|---|---|---|
| 5.2 | 3 | II | 8 | Beginner |
| 5.4 | 4 | III | 10 | Beginner |
| 5.5 | 5 | IV | 12 | Beginner |
| 5.7 | 5+ | V | 14 | Beginner |
| 5.9 | 6a | V+ | 17 | Intermediate |
| 5.10a | 6a+ | VI- | 18 | Intermediate |
| 5.10b | 6b | VI | 19 | Intermediate |
| 5.10c | 6b+ | VI+ | 20 | Intermediate |
| 5.10d | 6c | VI+ | 21 | Intermediate |
| 5.11a | 6c+ | VII- | 22 | Intermediate |
| 5.11c | 7a | VII | 23 | Advanced |
| 5.11d | 7a+ | VII+ | 24 | Advanced |
| 5.12a | 7b | VIII- | 26 | Advanced |
| 5.12b | 7b+ | VIII | 27 | Advanced |
| 5.12c | 7c | VIII+ | 28 | Advanced |
| 5.12d | 7c+ | IX- | 29 | Advanced |
| 5.13a | 8a | IX | 30 | Elite |
| 5.13b | 8a+ | IX+ | 31 | Elite |
| 5.13c | 8b | X- | 32 | Elite |
| 5.13d | 8b+ | X | 33 | Elite |
| 5.14a | 8c | X+ | 34 | Elite |
| 5.14b | 8c+ | XI- | 35 | Elite |
| 5.14c | 9a | XI | 36 | World class |
| 5.14d | 9a+ | XI+ | 37 | World class |
| 5.15a | 9b | XII- | 38 | World class |
| 5.15b | 9b+ | XII | 39 | World class |
| 5.15d | 9c | XII+ | 40 | World class |
Note: Grade conversions are consensus approximations. Rock type, style, and local conventions affect how grades feel in practice.
Historic Grade Milestones in YDS
The progression of hard grades tracks the history of sport climbing. Each barrier broken opened a new era:
- 5.10 — Long considered a mark of serious climbing ability; now accessible to dedicated beginners within a year or two.
- 5.11 — First established in the 1950s-60s at Yosemite; today a solid intermediate benchmark.
- 5.12 — Broke in the early 1970s; requires dedicated training for most climbers. Routes like "Midnight Lightning" (boulder) and "Separate Reality" were early 5.12 testpieces.
- 5.13 — Sport climbing in the 1980s pushed past this. Ron Kauk and John Bachar were early proponents.
- 5.14 — Wolfgang Güllich's "Action Directe" (1991) is widely recognized as the first true 5.14d. A tiny percentage of climbers worldwide can climb 5.14.
- 5.15 — Chris Sharma first proposed this grade with "Jumbo Love" (2008, 5.15b/9b). Adam Ondra's "Silence" (2017) is the only confirmed 5.15d/9c.
How Does YDS Compare to Today's Standards?
What was elite in 1985 is now accessible to advanced recreational climbers. The top 0.1% of climbers today operate at 5.14c–5.15d. A dedicated gym climber training regularly for 2–3 years might expect to break 5.11–5.12. 5.13 requires specific training and years of consistent practice for most people. 5.14 is a lifetime goal for most serious climbers.
Convert YDS Grades Instantly
Translate between Yosemite, Fontainebleau, UIAA and Australian grades with one click.
Open Grade Converter →Frequently Asked Questions
Why does YDS jump from 5.9 to 5.10 instead of 5.10 to 5.11?
When the system was created, 5.9 was the assumed limit of human climbing ability. Everything beyond it was grouped under "5.10" as an open-ended "extreme" grade. When climbers quickly showed that 5.10 wasn't the limit, the system kept expanding by adding more decimal places and letter suffixes rather than restructuring from scratch.
Is 5.10 considered easy or hard?
It depends on your experience level. 5.10 is solidly intermediate — it's where many recreational climbers plateau without dedicated training. For advanced climbers and professionals it's a warmup grade. Context matters: a pumpy 5.10 sport route feels very different from a technical 5.10 slab.
Why isn't there a 5.15c?
Grade gaps in the upper ranges reflect the practical reality that new routes at these levels are extremely rare. As of 2026, 5.15c has been proposed but not widely confirmed. The progression 5.15a (9b), 5.15b (9b+), and 5.15d (9c) reflects the Fontainebleau equivalent being used as the primary reference at the sport climbing frontier.
Does YDS apply to bouldering?
Technically no — bouldering in North America uses the V-scale (V0 to V17), developed by John "Vermin" Sherman at Hueco Tanks. YDS is specifically for roped climbing. The V-scale is roughly equivalent to Fontainebleau bouldering grades (Font 6a ≈ V1, Font 8a ≈ V11).