Key takeaways
- The UIAA grade rates climbing difficulty using Roman numerals (I, II, III...) with + and − modifiers.
- It's set by the UIAA and common in Germany, Austria, Switzerland, and Eastern Europe.
- Difficulty increases with the numerals; it's open-ended at the top.
- It corresponds via conversion to the YDS, French, and other scales.
From the UIAA (International Climbing and Mountaineering Federation).
What the UIAA grade is
The UIAA grade is a climbing difficulty rating system that uses Roman numerals (I, II, III… up through XII and beyond), with + and − modifiers, established by the UIAA — the international climbing and mountaineering federation. It rates the technical difficulty of free climbing and is commonly used in Germany, Austria, Switzerland, and Eastern Europe.
How it works
Difficulty increases with the numerals: roughly I–II very easy, III–IV moderate, and the higher numerals (VII, VIII, IX, X+) progressively harder, with + and − fine-tuning within each grade. Like other modern free-climbing scales, it’s open-ended, extending as standards advance.
A climber traveling to a crag in Germany sees routes graded VI+, VII−, and VIII. Using a conversion chart, they translate those UIAA grades into the YDS they’re used to, and pick routes matching their ability despite the unfamiliar Roman numerals.
How it compares
The UIAA grade corresponds via conversion to the YDS (5.x), the French scale, and others — they just use different notation. Our grade converter and the topic of grade conversion handle translating between them, including the bouldering Font scale.
The bottom line
The UIAA grade is the Roman-numeral climbing difficulty scale (I, II, III... with + and −) set by the international federation and common in Central and Eastern Europe. Open-ended and rising with the numerals, it rates free-climbing difficulty and maps via conversion onto the YDS and French scales — so a conversion chart lets you translate it when climbing across regions.
Frequently asked questions
What is the UIAA grade?
The UIAA grade is a climbing difficulty scale that uses Roman numerals (I, II, III, and so on, with + and − modifiers), established by the UIAA, the international climbing and mountaineering federation. It rates the technical difficulty of free climbs and is commonly used in Central and Eastern Europe, particularly Germany, Austria, and Switzerland.
How does the UIAA grading system work?
Difficulty increases with the Roman numerals — roughly I and II being very easy, III–IV moderate, and the higher numerals (VII, VIII, IX, X and up) being progressively harder — with + and − used to fine-tune within each grade. Like other modern free-climbing scales, it's open-ended, extending higher as climbing standards advance.
How does the UIAA grade compare to YDS and French grades?
All three rate free-climbing difficulty and correspond via conversion charts: for instance, UIAA grades map approximately onto the American YDS (5.x) and the French sport scale. The systems use different notation (Roman numerals for UIAA, decimals for YDS, number-letter for French), so climbers traveling between regions use a conversion chart or tool to translate.
Sources
- Grading systems — UIAA
- Climbing grades — American Alpine Club