Climbing Grade Converter - YDS, French, UIAA, V and Font

Every climbing grade on one ladder, from 5.4 to 5.15d and VB to V17

Is a 6c in Spain harder than the 5.11a you send at home? Pick the scale your guidebook uses, pick the grade, and this climbing grade converter returns the same route in YDS, French sport, UIAA, Ewbank, the Polish Kurtyka scale and the two-part British grade, with the three grades above and below it. Boulder problems convert between the V scale and Font, with a rough route equivalent. For the 6c the answer is 5.11a, so no, it is the same climb.

6 route scales

plus V and Font for boulders

30 rows

one for every YDS grade from 5.4 to 5.15d

5.12a = 7a+

where the sport scales start to line up

Converting a grade in three picks

Scale - the system written in your topo or guidebook: YDS in North America, French on bolted routes in most of Europe, UIAA in Germany, Austria and the Alps, Ewbank in Australia and New Zealand, Kurtyka in Poland. Boulder problems use V or Font. A lowercase letter (6a) means a route, an uppercase one (6A) a boulder.
Grade - choose it from the list, which holds only grades that exist on that scale, so a typo cannot slip in. In the example: French 6c.
Read the result - the main equivalent at the top, one tile per scale, and a table with your grade marked among its neighbors. A cell written as A/B means the grade sits between A and B.

Why there are so many scales

Each country that climbed early wrote its own ladder. The YDS grew out of the Sierra Club class system: class 5 is technical rock, and the number after the dot rises with difficulty, adding the letters a to d from 5.10 upward. The French scale took the UIAA idea and swapped Roman numerals for numbers with a, b, c and a plus. It grades the hardest move and nothing else, which is why it rules bolted sport climbing. UIAA grades in Roman numerals with plus and minus are still the norm in Germany, Austria and Switzerland and on alpine rock.

Two scales measure more than the moves. Ewbank, created by the Australian climber John Ewbank, is a single open-ended number that also weighs exposure, length, rock quality and protection. The British system uses two grades at once: an adjectival grade (VD, S, HS, VS, HVS, then E1, E2 and up) for the overall seriousness, and a technical grade (4a, 4b, 4c, 5a ...) for the hardest move. E4 is usually paired with 6a; an E5 6a has the same moves with less protection. That is why the British column in this converter is marked as indicative: it assumes a typical, reasonably protected route.

The Polish Cracow scale, proposed by Wojciech Kurtyka, keeps UIAA numerals up to VI+ and then counts VI.1, VI.1+, VI.2 and so on. Boulders have their own two systems. The V scale was published by John Sherman in his Hueco Tanks guide; Font comes from the sandstone of Fontainebleau and is written with a capital letter.

Route grades side by side, 5.8 to 5.14a

The rows come from the RockFax Rock Climbing Grade Table and theCrag, as compiled in the grade comparison of the English Wikipedia. A/B is a cell the source table leaves empty or spans across two rows; the converter reads it as between A and B.

YDS	French	UIAA	British	Ewbank	Kurtyka
5.8	5b	VI-	HVS 4c/5a	16	V
5.9	5c	VI	HVS/E1 5a	17	V+
5.10a	6a	VI+	E1 5a/5b	18	VI
5.10b	6a+	VII-	E1/E2 5b	19	VI+
5.10c	6b	VII	E2 5b/5c	20	VI.1
5.10d	6b+	VII+	E2/E3 5c	20/21	VI.1+
5.11a	6c	VII+/VIII-	E3 5c/6a	21	VI.2
5.11b	6c/6c+	VIII-	E3/E4 5c/6a	22	VI.2/VI.2+
5.11c	6c+	VIII-/VIII	E4 6a	23	VI.2+
5.11d	7a	VIII	E4/E5 6a/6b	23/24	VI.3
5.12a	7a+	VIII+	E5 6a/6b	24	VI.3+
5.12b	7b	VIII+/IX-	E5/E6 6b	25	VI.4
5.12c	7b+	IX-	E6 6b/6c	26	VI.4/VI.4+
5.12d	7c	IX	E6/E7 6b/6c	27	VI.4+
5.13a	7c+	IX+	E6/E7 6c	28	VI.5
5.13b	8a	X-	E7 6c/7a	29	VI.5+
5.13c	8a+	X-	E7/E8 7a	30	VI.5+/VI.6
5.13d	8b	X	E8 7a/7b	31	VI.6
5.14a	8b+	X+	E8/E9 7a/7b	32	VI.6+

The converter carries the full range in both directions, from 5.4 (French 4a, UIAA IV, Ewbank 10) to 5.15d (French 9c, UIAA XII+, Ewbank 39). The British column stops at E11 on 5.15a, the last row the source table fills.

Boulder grades: V, Font and a rough route equivalent

The second table is the bouldering half of the converter, from the RockFax Bouldering Grade Table and theCrag, with the route columns from a UIAA report. V and Font almost match; the route columns are the weak part.

V scale	Font	~ YDS	~ French sport
V0	4	5.9	6a/6a+
V1	5	5.10c/5.10d	6b/6b+
V2	5+	5.10d-5.11b	6b+/6c
V3	6A	5.11c	6c+
V4	6B	5.12a	7a/7a+
V5	6C	5.12b	7a+/7b
V6	7A	5.12c	7b+
V7	7A+	5.12d	7b+/7c
V8	7B	5.13a	7c/7c+
V9	7C	5.13c	8a/8a+
V10	7C+	5.13d	8b

Below V9 some Font grades have no V grade of their own: 6A+ sits between V3 and V4, 6B+ between V4 and V5, 6C+ between V5 and V6, and 7B+ between V8 and V9. From V9 = 7C upward each V grade has exactly one Font grade, up to V17 = 9A.

Patterns hiding in the tables

The low grades disagree the most. Up to about 5.12a the scales were built by different people on different rock, and the tables mostly differ by one step. From 5.12a, 7a+ and VIII+ upward, sport climbing took over and the French, YDS and UIAA columns line up almost exactly.

Font 6A is not French 6a. The same digits mean very different climbs. A boulder of Font 6A compares to a route of about 6c+, while a route of French 6a is a 5.10a. The capital letter is the only warning, which is why British guides write routes as f6a.

A British grade can move without the moves changing. E4 6a is the standard pairing; E5 6a has the same hardest move with sparser gear. The Indian Face in Wales, the first route given E9, is only 6c technically, which the route table puts beside 5.13a: the E9 is about the fall, not the crux.

Ewbank counts what YDS leaves to a suffix. Exposure, length and protection are already inside an Ewbank number, while YDS adds R or X for a dangerous route. Punks in the Gym at Mount Arapiles, graded 32, was the first route in the world at French 8b+, which the table lines up with 5.14a.

How far to trust a converted grade

Treat the answer as the same band of difficulty, not the same climb. Grades are opinions agreed on by the climbers who repeated a route, and local style matters as much as the number: slab, crack and steep pockets reward different skills. The sport columns of this converter are reliable to about one step at the lower end and closer above 5.12a. The British column is indicative, because the adjectival grade depends on protection. The route equivalents of boulder grades are rough: tables by different authors differ by several grades, because a short powerful problem and a long route test different things. Indoor gym grades are a further step removed; outdoor boulders often feel harder than the same number on plastic.

Grade conversion questions from the crag

What is V4 in French?

As a boulder grade, V4 is Font 6B. If you mean a sport route of similar effort, the tables put it at about 7a to 7a+ French, or 5.12a YDS, and that part is only a rough guide.

What is a 7a boulder on the V scale?

A boulder written 7A on the Font scale is V6. A 7a route is a different thing: French sport 7a is 5.11d YDS. Check whether the letter in the guide is capital or lowercase.

What does 5.11 mean in French grades?

The four letters of 5.11 cover 6c (5.11a) to 7a (5.11d), with 6c+ at 5.11c. A plain 5.11 in an older American guide is anywhere in that band.

How do British trad grades convert to YDS?

Only roughly. HVS sits near 5.8, E1 near 5.10a, E3 near 5.11a and E5 near 5.12a, for a route with a typical technical grade and reasonable gear. Read the technical grade too: an E5 6a is a bold 5.11, not a safe 5.12.

How do Australian Ewbank grades compare to YDS?

On the table, Ewbank 18 sits beside 5.10a, 21 beside 5.11a, 24 beside 5.12a, 28 beside 5.13a and 32 beside 5.14a. In the middle of the scale one Ewbank number covers roughly one YDS letter. Keep in mind that an Ewbank grade also carries the length, the exposure and the gear of the route, so a run-out 21 can feel harder than a well-bolted 5.11a.

Why do some grades show up as A/B?

The scales do not have the same number of steps. Between 5.10a and 5.12a YDS counts nine grades, and the source table leaves two of their UIAA cells empty. Where the source leaves a cell empty or stretches one grade over several rows, the converter writes the two neighbors, for example VII+/VIII- for 5.11a, rather than inventing a step the scale does not have.

Why does my UIAA conversion differ from another chart?

UIAA charts disagree most between French 6a and 7a, where some put 6b at VII- and others at VII. This converter uses one source for every column, RockFax and theCrag, so its rows agree with each other even where another chart is one step off.

What is the hardest grade climbed so far?

On routes, 9c, which is 5.15d and UIAA XII+, first given to Silence in Norway. On boulders, 9A, which is V17, first given to Burden of Dreams in Finland. Both sit on the last rows of this converter.

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