thumb|[[Action Directe (climb)|Action Directe was a major milestone in free climbing grades when Wolfgang Güllich freed it in 1991 at 9a (French), 5.14d (American YDS), XI (UIAA).]]

Many climbing routes have grades to calibrate the technical difficulty, and in some cases the risks, of the route to the climber. The first ascensionist can suggest a grade but it will be amended for the 'consensus view' of subsequent ascents. While many countries with a tradition of climbing developed their own grading systems, a small number of grading systems have become internationally dominant for each type of climbing, and which has led to the standardization of grading worldwide. Over the years, grades have consistently risen in all forms of climbing, helped by improvements in climbing technique and equipment.

In free climbing (i.e. climbing rock routes with no aid), the most popular grading systems are the French numerical or sport system (e.g. 7c+), the American YDS system (e.g. 5.13a), and latterly the UIAA scale (e.g. IX+). These systems solely grade the technical difficulty and are used for the lower-risk activity of sport climbing. The American system adds an R/X suffix to calibrate the additional risks of traditional climbing routes. Notable traditional grading-systems include the British E-grade system (e.g. E4 6a).

In bouldering (i.e. rock climbing on short routes), the popular systems are the American V-scale (or "Hueco") system (e.g. V14), and the French "Font" system (e.g. 8C+). The Font system often attaches an "F" prefix to further distinguish it from French sport climbing grades, which itself uses an "f" prefix (e.g. F8C+ vs. f8c+). It is increasingly common for sport-climbing rock-routes to describe their hardest technical movements in terms of their boulder grade (e.g. an f7a sport climbing route being described as having a V6 crux).

In aid climbing (i.e. the opposite of free climbing), the most widely used system is the A-grade system (e.g. A3+), which was recalibrated in the 1990s as the "new wave" system from the legacy A-grade system. For "clean aid climbing" (i.e. aid climbing equipment is used but only where the equipment is temporary and not permanently hammered into the rock), the most common system is the C-system (e.g. C3+). Aid climbing grades take time to stabilize as successive repeats of aid climbing routes can materially reduce the grade.

In ice climbing, the most widely used grading system is the WI ("water ice") system (e.g. WI6) and the identical AI ("alpine ice") system (e.g. AI6). The related sport of mixed climbing (i.e. ice and dry-tool climbing) uses the M-grade system (e.g. M8), with other notable mixed grading systems including the Scottish Winter system (e.g. Grade VII). Pure dry-tooling routes (i.e. ice tools with no ice) use the D-grade prefix (e.g. D8 instead of M8).

In mountaineering and alpine climbing, the complexity of the routes requires several grades to reflect the difficulties of the various rock, ice, and mixed climbing challenges. The International French Adjectival System (IFAS, e.g.TD+) – which is identical to the "UIAA Scale of Overall Difficulty" (e.g. I–VI) – is used to grade the 'overall' risk and difficulty of mountain routes (with the gradient of the snow/ice fields). For example, the 1938 Heckmair Route on the Eiger is graded: ED2 (IFAS), VI− (UIAA), A0 (A-grade), WI4 (WI-grade), 60° slope. Related 'commitment grade' systems include the American National Climbing Classification System (e.g. I–VI).

History

thumb|The six levels (Grade I–VI) of the "Welzenbach scale", from 1926

In 1894, the Austrian mountaineer introduced the first known climbing grading system, which he introduced to rock climbing. The "Benesch scale" had seven levels of difficulty, with level VII the easiest and level I the hardest; as more difficult climbs were made, the grades of level 0 and level 00 were added.

In 1923, German mountaineer compressed the scale and reversed the order so level 00 became level IV–V, and it became popular in the Alps. In 1967, the "Welzenbach scale" formally became the "UIAA scale" for rock climbing (or "UIAA Scale of Difficulty") with Roman numerals I–VI, and a "+" and "−" to refine each level. The UIAA also incorporated proposals made in 1943 by and the on a broader "Scale of Global Assessment" for alpine climbing (the French Alpine System), and created the "UIAA Scale of Overall Difficulty" by assigning Roman numerals I–VI to the six adjectival levels (e.g. F, PD, AD, D, TD, and ED) of the French system. The UIAA also incorporated a "Scale of Difficulty in Aided Climbing" for aid routes with the levels: A1, A2, A3, A4, and (later) A5. In 1978, the UIAA added the VII (seventh grade) to its "UIAA scale", implying that the scale was open-ended, a concept formally adopted in 1985.

Free climbing

thumb|[[Adam Ondra on the sport climbing route Silence, one of the hardest free climbing routes in the world and the first-ever proposed at 9c (French), 5.15d (American YDS), and XII+ (UIAA).]]

Free climbing is a form of rock climbing in which the climber can use their rock-climbing equipment only for their protection, not as an artificial aid to help them in ascending a climbing route. The two main free climbing grading systems (which include the two main free climbing disciplines of sport climbing and traditional climbing) are the "French numerical system" and the "American YDS system".

American big wall climbing routes will often include the NCCS grade (Levels I–VII) with the YDS grade (e.g. the Salathé Wall at 5.13b VI).

The UIAA scale is closely aligned with the French system up to Grade V+, which is French grade 5a, but thereafter begins to diverge, although the two can be reasonably aligned in comparison tables.

British E-grade

thumb|The crag of [[Clogwyn Du'r Arddu in Wales with Indian Face (centre), which was the first-ever E9-graded route on the British system at E9 6c (British) or 5.13a X (American)]]

The most complex grading system is the British E-grade system (or British trad grade), As of April 2026, the highest consensus E-grade on a traditional route in Britain was on Lexicon (E11 7a) and on Rhapsody (E11 7a), which are equivalent to American 5.14 R or French f8b+/f8c+. Outside of Britain, the highest E-grade was Bon Voyage in France at E12, or 5.14d / 9a.

The first grade is an "adjectival grade" that covers the overall difficulty of the route and takes into account the: "seriousness, sustainedness, technical difficulty, exposure, strenuousness, rock quality, and any other less tangible aspects which lend difficulty to a pitch". British climbers use the prefix "f" to distinguish French sport-grades from British technical grades, which is important as they are not equivalent (e.g. British 5c is f6b+). E5 6a indicates that the risk is higher (i.e., closer to an American YDS "R"), while E6 6a indicates a very significant risk (like the American YDS R/X), and a rare E7 6a means effectively no protection (similar to a full American YDS "X" or essentially a free solo route).

  • Polish Cracow scale (or Kurtyka's scale). Up until the 1970s, the UIAA scale was used in the limestone climbing areas near Kraków, where Polish sport climbing was developed, with Grade I (easiest) to Grade VI (hardest). As the climbing level grew, the UIAA scale became inadequate. Polish climber and alpinist Wojciech Kurtyka proposed an extension to the scale. Easier routes were described by the UIAA scale, and harder routes above Grade VI+ used Arabic numerals with a "+" refinement, so that after Grade VI+ came the new grades of: VI.1, VI.1+, VI.2, VI.2+, and so on.
  • Deep-water soloing grades. A number of systems have been used to assign a "risk" grade for deep-water soloing routes (they typically use the French grading system or American YDS system for the technical challenge). Notable examples include the British S-grades (e.g. S0, S1, S2, S3), which covers the objective risk of the route including tides, under-water objects, height of any potential fall etc.

Bouldering

thumb|[[Dreamtime (climb)|Dreamtime follows the diagonal green line, and Somnolence follows the vertical blue line]]

The two main boulder grading systems are the French Font-grade and the American V-grade systems.

As of May 2026, the hardest bouldering grade is V17 / Font 9A. Burden of Dreams, in Lappnor in Finland, was the first-ever boulder to be given that grade.

Comparison with free climbing

The Font-grade system is easily confused with the French sport grade and the British E-grade systems as they use similar symbols, but boulder grades are very different from free climbing grades and they start at much harder technical levels. For example, the entry-level Font-grade 4 / V-grade V0 is equivalent to the free climbing grades of 6a to 6a+ (French), VI to VII− (UIAA), and 5.9 to 5.10c (American YDS), depending on what table is used.

This confusion is amplified by the tendency for modern sport-climbers to describe the crux moves on their routes in terms of their bouldering grades – their routes are effectively a series of connected boulder problems. For example, here is Adam Ondra describing his 2017 redpoint of Silence, the first-ever free climb in the world to carry a grade of 9c (French), 5.15d (American), XII+ (UIAA):

thumb|Climber on Rave Heart section of [[The Wheel of Life, which is graded at a boulder route at , and a free climbing route at f9a (5.14d)]]

In addition, boulder routes that connected various boulder problems into a single longer bouldering route have been graded as if they were sport climbs. A notable example is the 2004 boulder route The Wheel of Life, which is graded as a boulder route, but also f9a (5.14d) as a sport climbing route.

Font grade

The Font-grade (from the "Fontainebleau climbing area") is one of the oldest boulder grading systems whose origins can be traced back to at least 1960 with Michel Libert's L'Abbatoir at Fontainebleau.

  • British Peak B-grade. The Peak District in Britain is an important bouldering area and had developed a bouldering scale that was very similar to the V-grade scale except the pre-fix "B" was used and it started at B1 (i.e. B1, B2, B3, B4, ... etc.). Peak B-grades are roughly one level easier than V-grades (e.g. V8 was equivalent to B9). The V-grade / Font-grade systems (sometimes the "technical grade" component of the British E-grade system is used) have replaced Peak B-grades in Britain but they appear in some guidebooks and some boulder grade conversion tables.

Aid climbing

The main aid climbing systems are the A-grade (usually the "new wave" version) and the C-grade systems.

Instability of aid grades

thumb|[[Layton Kor on the first ascent of Exhibit A Eldorado Canyon; the route was then graded 5.9 A4 (original A-grade), but is now graded 5.8 C2+ R (post "new-wave" C-grade).]]

The grade of an aid climbing route can change materially over time due to improvements in aid equipment but also due to the impact of repeated ascents. It is not uncommon for a new A5 route in Yosemite to become a "beaten-out A3+ route" due to the effect of repeated hammering of cracks (which widens them), and to the build-up of permanent in-situ aid climbing equipment, from successive teams.

Original A-grade

The original "UIAA Scale of Difficulty in Aided Climbing" system went from A0 to A5 and focused on the number and quality of "bodyweight placements" (i.e. can only take static bodyweight and not a falling bodyweight) versus "bombproof placements" on a given pitch.

In 2010, ice climbers began to put up new ice routes at Helmcken Falls in Canada that had unique characteristics. Unlike the sheerest WI7 ice routes, these routes were significantly overhanging like extreme M-graded routes. This was due to the intense spray from the waterfall, which covered the overhanging routes in ice so that there was little dry-tooling (i.e. all the movement was on hard ice).

M-grade

thumb|Rocket Man (M9), Wyoming. Many M-grade routes are really a combination of a WI-grade ice route and a D-grade dry tooling route.

The grading of mixed climbing routes approximates the ice climbing WI grades, up to M6, but they then diverge as mixed routes can become very overhanging and eventually turn into roofs (ice is not normally overhanging, aside from Helmecken Falls routes).

In his 1996 book, Ice World, mixed climbing pioneer Jeff Lowe ranked his new M-grades to the level of physical exertion needed on a free rock climb; for example, Lowe estimated that M8 was equivalent to 5.12 (American YDS). and now equate M8 to 5.10/5.11, but there is some variation and no consensus that such comparisons are valid.

D-grade

When mixed climbing is done as pure dry-tooling, which is ice climbing on bare rock with no ice section, the M-grade is usually replaced by a "D" grade prefix (but all other aspects of the two systems are identical).

Scottish winter grade

thumb|Greg Boswell on the first ascent of Banana Wall, the second-ever Scottish Winter Grade XII/12 route.

Mixed climbing in Scotland is known as "Scottish Winter climbing" and uses a dual-grading system – similar to the British E-grade – with a Roman numeral denoting the "overall" difficulty (e.g. technical challenge, length, and the level of boldness/physicality/stamina required).]]

The most important grading system in mountaineering is the International French Adjectival System (IFAS) (or French Alpine System, FAS), which is also effectively the "UIAA Scale of Overall Difficulty" (they are the same, only differing in labels), and which is used in all forms of alpine climbing around the world.

Due to the complexity and length of mountaineering and alpine climbing routes, their grading systems focus on the "overall" risk and/or commitment of the route.]]

In the "Alaskan Overall Difficulties" system, Various authors have created tables to compare bouldering grades of Font/V-grade, to the free climbing French sport/American YDS grades, but because of the different types of climbing (and particularly the sequences of movements), they are only ever indicative and can vary by several levels between versions; and UIAA (2021).