Bouldering V-Scale Converter

About This Tool

The Bouldering V-Scale Converter translates between the three grading systems used worldwide for boulder problems: the V-scale (also called Hueco scale) used in the United States, the Fontainebleau system used across Europe and most international competitions, and the Hueco scale, which is functionally the same as the V-scale. If you climb at gyms with mixed-system tape, travel to European destinations like Fontainebleau or Magic Wood, or watch international climbing competitions, this converter saves time.

Origins of the V-Scale

John “Vermin” Sherman developed the V-scale at Hueco Tanks State Park in Texas during the 1980s and early 1990s. He needed a way to grade the explosion of new boulder problems being established at Hueco, and existing systems didn't fit the style of climbing he and his peers were doing. The V stands for Vermin, his nickname. Starting at V0 and originally topping out at V13, the scale has expanded as world standards rise. V17, currently the hardest confirmed grade, was proposed for Burden of Dreams in Lappnor, Finland, established by Nalle Hukkataival in 2016.

The Fontainebleau System

The Font system grew up in the sandstone forest of Fontainebleau, France, the world's most famous bouldering destination. It uses numbers from 3 (easy) to 9A (hardest), modified with sub-letters A, B, C and optional plus signs. The Font system has finer granularity than V-scale at intermediate grades: V3 covers both Font 6A and 6A+, V4 covers both 6B and 6B+. Many strong boulderers prefer Font grades for this reason.

How Conversions Work

Conversions between V-scale and Font are approximate, especially at lower grades where the systems started independently. From V3 / 6A upward, conversions are well-established consensus from major guidebooks and the Mountain Project / 8a.nu databases. Below V3, there's significant overlap and ambiguity because grades that low are usually new climbers feeling around. Don't over-rotate on whether your gym's V2 is actually 5+ or 6A. Just climb.

Reading Boulder Problem Difficulty

Boulder grades reflect raw difficulty for short, gymnastic sequences. A typical boulder problem is 4-12 moves long. Crucially, boulder grades don't factor in route length, exposure, or pump like roped climbing grade systems do. A V8 boulderer can be much weaker on 5.13a sport routes if they lack endurance, and vice versa. Strong sport climbers who try bouldering for the first time often find themselves multiple V-grades below their endurance level.

Boulder Grading Is Subjective

Grades are consensus estimates from local climbers and guidebook authors. They vary by region, rock type, and even the height of the first ascensionist. Tall climbers find some problems easier (longer reach, better leverage), while short climbers crush other problems (better fit through bunched-up moves). Crystal grippy granite at Joshua Tree feels nothing like glassy Fontainebleau sandstone. Treat conversion charts as starting points, not gospel.

Plan Your Bouldering Day

Once you've got your grade dialed, plan the rest of your trip with our approach hike calculator, our backpack weight calculator for crash pads and gear, and our water needs calculator for the desert sessions where dehydration kills sends. For roped climbs after the boulder session, hit our climbing grade converter.