How to Convert Bouldering Grades: Bouldering Grade Ranges

Bouldering grades are systems that determine the level of difficulty of a bouldering route (often called a “boulder problem”), graded based on its hardest move rather than as an average difficulty. The bouldering grade system used in the United States is the V Scale, which uses a basic numbering system, with small numbers (as low as 0) designating easier routes and higher grades (up to 17) designating more challenging routes.

The most popular grading system outside of the US is the Font Scale (short for Fontainebleau Scale). This scale uses both a number range (1 being the easiest and 9 the most challenging) and letter grades to illustrate nuance within each numeral (A being the easiest and C the hardest) and occasionally a plus symbol (+) to designate increased difficulty.

Both outdoor climbing and indoor climbing utilize bouldering grades. The grades for outdoor climbing areas are often much more subjective since the climbers that have successfully made the ascent determine them. Indoor climbing ratings are usually more standardized (especially within a single bouldering gym) since staff members (called “setters”) who install the handholds determine them.

The first recorded bouldering grade system was conceived by climber John Gill, who designed a simple three-rank scale that he called the B Scale, in which rock climbs could either be rated B1, B2, or B3. However, he reserved the B3 designation for climbs that had been climbed only once, resulting in climbs being re-graded after additional successful climbs. Climbers considered his scale too confusing, and it never saw wide use.

The first successful bouldering grade system was the V Scale, conceived by climber John Sherman, whose nickname “Verm” (short for “Vermin”) inspired the scale’s name. Sherman spent time bouldering in Hueco Tanks, Texas, and realized that a consistent rating system for measuring bouldering problems would help new climbers and veteran climbers alike. John “Verm” Sherman’s first use of the V grading scale was published in a guidebook to the boulders in Hueco Tanks.

In the US, the V Scale is the most common unit of measurement to decide bouldering difficulty. Here are the general ranges of each bouldering rating:

1. 1. V0 through V2: The numbers on the lower end of the scale are associated with easy or beginner bouldering routes. Sometimes, you may see a climb labeled “VB”—the B stands for “beginner” and is often used interchangeably with V0. These climbs are usually considered equivalent to climbs 3 through 5+ on the Font Scale.
2. 2. V3 through V6: The numbers 3 through 6 on the scale represent intermediate bouldering routes, requiring a more moderate amount of athleticism and skill than easy routes but still attainable by early boulderers. Most casual boulderers climb between V4 and V7 routes. Intermediate routes are usually considered equivalent to climbs 6A/+ through 7A on the Font Scale.
3. 3. V7 through V10: The routes with a V grade labeled 7 through 10 are advanced. These routes are usually the most challenging that an unprofessional boulderer can climb and are usually considered equivalent to climbs 7A+ through 7C+ on the Font Scale.
4. 4. V11 through V17: The routes with technical grades between 11 and 17 are considered professional bouldering routes. They are very difficult routes only climbable by boulderers who have dedicated a significant portion of their time to training and preparation. These climbing routes are usually considered equivalent to climbs 8A through 9A on the Font Scale.

The two bouldering grading systems are the V Scale (used in the United States) and the Font Scale (used outside the US). Grade conversion between the two scales isn’t easy—the Font Scale has more grade options than the V Scale, and both scales are subject to regional differences and individual climbers’ body types, opinions, and skill sets—but in general, here’s how the two scales compare:

• V Scale VB = Font Scale 3
• V Scale V0 = Font Scale 4
• V Scale V1 = Font Scale 5
• V Scale V2 = Font Scale 5+
• V Scale V3 = Font Scale 6A or 6A+
• V Scale V4 = Font Scale 6B or 6B+
• V Scale V5 = Font Scale 6C or 6C+
• V Scale V6 = Font Scale 7A
• V Scale V7 = Font Scale 7A+
• V Scale V8 = Font Scale 7Bor 7B+
• V Scale V9 = Font Scale 7B+ or 7C
• V Scale V10 = Font Scale 7C+
• V Scale V11 = Font Scale 8A
• V Scale V12 = Font Scale 8A+
• V Scale V13 = Font Scale 8B
• V Scale V14 = Font Scale 8B+
• V Scale V15 = Font Scale 8C
• V Scale V16 = Font Scale 8C+
• V Scale V17 = Font Scale 9A

While the main bouldering grading systems are the V Scale and the Font Scale, rope climbing (including sport climbing, top-rope, and trad leading) has its own set of grading systems: the Yosemite Decimal System, or YDS (used in North America), and the French Scale or French System (used outside North America).

The bouldering and climbing grades outside the US (the Font Scale and French Scale) are easy to convert since they use the same letters and numbers. However, the V Scale and YDS use different intervals, meaning that conversion between the two is more nuanced and less straightforward.

Climbing is a high-impact activity with an elevated risk of serious injury. Practice, proper guidance, and extensive safety precautions are essential when attempting a climbing pursuit. This article is for educational and informational purposes only and is not a substitute for professional instruction or guidance.

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