Bouldering grades explained: the Fontainebleau and V scales

A bouldering grade assesses moves, not length

Bouldering scales describe the technical difficulty of the movements — and nothing else. No risk component, no protection, no endurance over a pitch. A boulder consists of few but very hard moves; a roped route of many easier ones in a row.

That sounds like a detail, but it has a hard consequence: bouldering and roped climbing grades do not measure the same thing and cannot be converted into one another. Anyone writing both into the same table is systematically miscalculating — and anyone adding up numbers from both worlds is adding things that have nothing to do with each other.

Two scales, you do not need more

There are more systems worldwide, but day to day you will meet two. Which one hangs in your gym simply depends on which tradition it follows.

Both scales are open-ended. Which Font grade corresponds to which V grade is set out in full in the climbing grade converter — the same table here would be a second copy, and two tables can only drift apart.

Where the Fontainebleau scale comes from

In the forest of Fontainebleau south of Paris, sandstone blocks lie scattered among the trees. Members of the Club Alpin Français, founded in 1874, were already training there for the Alps — at that point bouldering was not a sport of its own but preparation for the mountains.

In 1947 Fred Bernik invented the boulder circuit there: a string of up to 50 boulders, numbered, colour-coded and climbed one after another. Anyone climbing a “circuit” in a single hold colour in a gym today is following an idea that started in that forest.

The scale itself can be traced back to at least 1960 and “L’Abbatoir” by Michel Libert. It starts at 1 and rises in steps of one, with a “+” in between for a finer gradation. From grade 6 upwards the capital letters A, B and C are added — giving the sequence 6A, 6A+, 6B, 6B+, 6C. The German-language overview article additionally distinguishes Fb-Bloc for individual boulders and Fb-Trav for traverses. Today the scale is used in Europe, Russia, Asia and South Africa.

Where the V scale comes from

The American line begins with John Gill, often called the father of modern bouldering. In the late 1950s he combined gymnastics with climbing, introduced chalk for keeping the hands dry, promoted a dynamic style of movement and emphasised strength training. His essay “The Art of Bouldering” appeared in the Journal of the American Alpine Club in 1969 and counts as the founding text of the discipline.

Gill’s grading system, however, was closed: B1 denoted boulders as hard as the hardest roped routes of his time, B2 was harder, and B3 stood for a boulder that had so far been climbed exactly once. Such a system has a built-in contradiction — it measures the state of the sport against itself and shifts as soon as somebody climbs better.

In 1991 John “Verm” Sherman published the V scale in the “Hueco Tanks Climbing and Bouldering Guide”. It is open-ended, starts at V0 and also knows VB for beginner boulders. Unlike Fontainebleau it works without intermediate steps in the lower range: V1 is followed by V2, not V1+. The highest grade awarded so far is V17.

The most common error: 7A is not 7a

Fontainebleau and the French sport climbing scale both come from France and use the same digits. They are distinguished only by how the letter is written: capital in bouldering, lower case in sport climbing. Font 7A is a boulder, French 7a is a roped route, and the two sit well apart.

That is precisely why this page carries no comparison between bouldering and roped climbing grades. Tables offering one do exist — but they describe themselves as merely indicative and admit that the match can vary by several grades. A number allowed to be several grades out is not an answer.

Where Fontainebleau and the V scale diverge

Within bouldering, on the other hand, the two scales can be compared, and better than the roped climbing scales can be compared with each other: from 7C or V9 upwards they match exactly. Below that, Fontainebleau is more finely graded — it has intermediate steps for which the V scale has no value of its own.

At such points the converter therefore shows not a single value but both neighbours. That looks like a weakness, but it is the more honest statement: a range claims exactly as much as the scale supports.

Who decides the grade

It starts with a proposal from the first ascensionist. It only becomes binding through the consensus of those who repeat it. How long that can take is shown by the hardest boulder in the world at present: Nalle Hukkataival climbed “Burden of Dreams” in Lappnor near Loviisa in Finland on 23 October 2016, after four years of work on it, and proposed 9A or V17 — the first grade of that level worldwide, 8C+ having been the highest before.

The grade was only confirmed six and a half years later: Will Bosi made the first repeat on 12 April 2023. Further ascents followed — and in May 2026 Noah Wheeler assessed the boulder as a “soft” 9A. That is exactly consensus at work: a grade without a repeat is a proposal, and even afterwards it stays negotiable.

On top of that comes something no scale can resolve: height, arm length, flexibility and other physical characteristics affect how hard a boulder turns out to be for a particular person. Individual grades are therefore often disputed without either side being wrong.

Gyms follow a calculation of their own

In bouldering gyms, grading usually happens via the colour of the holds or via cards attached to them. Some gyms group boulders into “circuits”: a set of the same grade or a band spanning two to three grades, often identifiable by a single hold colour. The grades behind them follow the same scales as on rock.

Two limitations are worth knowing. First, indoor boulders are considered to be graded more softly than comparable boulders outdoors up to about V10 or Font 7C+; above that range the difference disappears. Second, gyms differ from one another: the British governing body states explicitly that a grade depends on the person climbing as much as on the person setting and can hardly be standardised — grades usually feel similar from gym to gym, but you cannot rely on it.

So changing gym shifts your familiar numbers without anything about your performance having changed. That is not a step backwards, but a different yardstick.

Frequently asked questions

What does the plus in a Fontainebleau grade mean?

It is an intermediate step. The Fontainebleau scale starts at 1 and rises in steps of one; the “+” inserts a finer gradation in between, so 6A, then 6A+, then 6B. From grade 6 upwards the capital letters A, B and C are added as well. This makes Fontainebleau considerably more finely graded in the lower and middle range than the V scale, which knows only whole numbers there.

Why are Font grades written with a capital and French sport grades with a small letter?

Because they are two different scales that happen to use the same digits. Fontainebleau grades boulders and capitalises the letter: 6A, 7A, 8A. The French sport climbing scale grades roped routes and uses lower case: 6a, 7a, 8a. Font 7A and French 7a are not the same and sit well apart. This is the most common mix-up when reading topos and gym labels.

Can I convert my bouldering grade into a route grade?

Not meaningfully, and this page therefore gives no value for it. Bouldering grades assess the technical difficulty of a few moves; route grades assess a sequence of many easier moves across a whole pitch. The sources that do offer such comparisons describe them themselves as merely indicative and as varying by several grades. That is why the climbing grade converter on this site strictly separates bouldering and roped climbing and converts only within one discipline.

Why does the same grade feel harder outdoors than indoors?

Because indoor boulders are considered to be graded more softly than comparable boulders on rock up to about V10 or Font 7C+. Above that range the difference disappears, because most climbers then have outdoor experience anyway. On top of that, gyms differ from one another: a grade depends on the person climbing as much as on the person setting, and can hardly be standardised.

Why do two people find the same boulder differently hard?

Because a bouldering grade does not only describe the moves; it always describes the relationship between the moves and a body. Height, arm length, flexibility and other physical characteristics affect how hard a boulder turns out to be for a particular person. Individual grades are therefore often disputed — even when everyone involved climbs equally well.

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