Climbing grades compared: French, UIAA, YDS and British

What does a climbing grade actually tell you?

Picture a Saturday morning at the foot of an indoor wall, where a tag on the first hold says 6a. A few weeks later, an American guidebook writes the same difficulty as 5.10a. Same route, same level? Roughly. And that ‘roughly’ deserves a moment before you compare your numbers with your mates’, who will round in their own favour.

A grade answers one question only: how hard is the hardest part? The French mountaineering and climbing federation (FFME) describes it as an index of the difficulty of the boulder problems or routes you are taking on [3]. An index, then, not a measurement: it says nothing about height, the danger of a fall or the quality of the protection.

Where does the number come from? The first person to climb the route proposes a grade, and those who follow adjust it. A German coach and guidebook author, Markus Stadler, reckons a grade settles after five to ten repeats: it is an average of subjective opinions, not an instrument reading [7]. The UIAA adds that difficulty is judged in the ideal conditions of the rock face: on wet rock, the same route is a different animal [2].

Which four scales are worth knowing?

There are others (the Elbe sandstone scale, the Scandinavian scales, the Australian one...) [1] [2], but four will let you read most of the guidebooks you are likely to meet.

• France: A number from 3 to 9, followed by a letter a, b or c and sometimes a +. A 6c+ route is harder than a 6c and easier than a 7a. For bouldering, the FFME uses the same system, from 1b to 8c [3].
• UIAA: Roman numerals with + and -. The scale became official in 1967, VII was recognised in 1978, and the scale was opened upwards in 1985 [1].
• United States (Yosemite Decimal System, YDS): Five classes, of which only the fifth is technical climbing; it is subdivided from 5.0 to 5.15, with letters from a to d from 5.10 upwards [4] [6]. A route’s class comes from its hardest section, the crux [6].
• United Kingdom: Two parts: an adjective (Moderate, Difficult, Severe, Very Severe, then E1, E2...) for the route as a whole, and a technical grade (4a, 4b, 5a...) for the hardest move [5].

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The conversion chart, and why to be wary of it

Here is a conversion table, built from the Mountain Project grid and cross-checked against the UIAA’s [4] [2]. Read it as a neighbourhood: each row brings together grades that are close, not identical.

The tables do not always agree. The UIAA’s ‘pleasure’ table, drawn from the archives of Gino Buscaini, puts V+ at 5b; Mountain Project puts it at 5a [2] [4]. The UIAA also admits that 6a, first matched with VI+, is now matched with VI, depending on the place and the regulars [2]. It presents its own equivalences as approximate rather than absolute [1].

The same caution applies on the British side: the BMC pairs S with 4a on average, HS with 4b, VS with 4c, HVS with 5a, E1 with 5b and E2 with 5c, then adds that these rules are broken more often than they are followed [5]. And do not mistake the bottom of the scale for a playground: the Swiss Alpine Club describes V as a level at which the long high-mountain routes already count among the big undertakings of the Alps [9].

Is a 6a indoors the same as a 6a on a crag?

Not necessarily. Markus Stadler points out that the character of a route should not matter, but that an overhang with good holds and a wide crack are hard to compare, and that everyone ends up specialising [7]. After a long approach, far from the last piece of protection, almost nobody pulls the same moves as at the foot of a short crag, with the last quickdraw at knee height [7].

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The same author notes a trend towards more ‘human’ grades at recent crags: you are surprised how well you climb, then find harder grades again on the classics [7]. Conversely, the first route of a new grade is often rated severely, to justify the grade [7]. In the United States the debate is the same: some grades are judged too high or too low because standards have moved [6].

Difficulty and commitment: what a grade does not say

A grade gives the difficulty of one move. It does not tell you what you are committing to: length, remoteness, quality of protection, descent. Each country answers that in its own way [8].

• France (and across the Alps): On adventure terrain or in the high mountains, a qualitative overall grade: F (facile, easy), PD (peu difficile, not very difficult), AD (assez difficile, fairly difficult), D (difficile, difficult), TD (très difficile, very difficult), ED (extrêmement difficile, extremely difficult), ABO (abominable) [3]. The FFME also distinguishes sport routes, permanently equipped to its standards, from ‘adventure terrain’ routes, which are not [3].
• United States: The National Climbing Classification System rates the time required: Grade I takes less than half a day of technical climbing, Grade V generally a night on the route, and Grade VII covers big, remote walls [8]. Guidebooks may add a rating for seriousness [8].
• United Kingdom: The adjective already blends seriousness, length of effort, exposure, quality of rock and technical difficulty. A technical grade that is low for the adjective (HVS 4c, E3 5b) signals a very sustained route, or an easy one in a serious position [5].
• Aid climbing: A separate scale, from A0 to A5, based on how hard it is to place good-quality protection [3].

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Starting out: indoor walls, clubs and instruction

This article explains how to read numbers; it does not teach you to climb. The way in is an artificial structure (a bouldering centre, an equipped wall), with a club or a qualified instructor. In Britain, Mountain Training runs two relevant qualifications, which the BMC explains [11]. The Climbing Wall Instructor trains and assesses people to supervise climbers on artificial walls and boulders, and the Rock Climbing Instructor covers supervising climbers on single-pitch crags and on walls, with roped climbing and bouldering as everyday activities [11]. Neither includes teaching lead climbing [11].

On a crag, climbing means a rope and specific belaying equipment, in a natural setting that is never uniform and can send rocks down [3]. The FFME is blunt about it: by using these sites, climbers accept the normal and reasonably foreseeable risks of the activity [3].

Before you set off: how to read a grade

1. Identify the scale in use: the guidebook key will say (6a and VI are not the same thing).
2. Check whether the grade covers the whole route or only the hardest move.
3. Look for a commitment rating: an overall grade (F to ED), a grade for duration, or the British adjective.
4. Do not convert in your head: a chart gives a neighbourhood, never an equality.
5. Ask your instructor what that number means at that particular crag.

A good habit to get into fits in one sentence: a grade answers ‘how hard is the hardest move?’, never ‘should I go up there?’. The second question is one for you and your instructor, not for a chart.

Worth watching

A short magazine-style episode that decodes the grading systems used around the world and explains why countries grade differently, a spoken companion to our comparison of the scales.

The video is hosted by YouTube (Google): nothing loads until you play it, and Google may then set cookies.

Guillaume Hoarau

Camping, wild camping, bushcraft and hiking

Guillaume Hoarau writes for Outfarer about camping, wild camping, bushcraft and hiking. A survival-skills enthusiast and a collector of old field manuals, he likes clear explanations, lists that earn their place and other people’s stories, which he tells well.

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