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International climbing grades explained

Learn how to make sense of the different systems used for grading rock climbs and boulders

example of comparable grades

Few things are more likely to cause a disagreement between climbers than climbing grades. In fact, with the exception of a bad belay, nothing will do more to irritate your partner than a debate regarding the difficulty of their last hard send. But, there’s more at stake in this numbers game than just ego. In this article, I look at why grades are important and then delve into the even trickier business of translating one grading system into another.

Just numbers

It’s very easy for the single-pitch sport climber to say ‘it’s just a number.’ If he bites off more than he can chew, he can retreat by simply swapping out the top quickdraw for a quick link and lowering off. But it’s more difficult to abort when you’re 300 feet off the ground and there’s not a single piece of fixed gear in sight.

Given the risk of an epic, most climbers want to know what they’re getting themselves into before casting-off on a committing multi-pitch route. And many follow the best practice of starting with a few easy routes when visiting an area for the first time. This way you can get a feel for the rock and grades before committing to more serious routes.

‘Old school’ grades

Ideally, a route graded 5.10a would feel as difficult as a 5.10a at another crag. But nothing is that simple or convenient. Besides the difficulty in ensuring consistent grading across different types of rock, there will always be problems with subjectivity, and even the grades at similar crags can differ wildly (Just ask anyone who has climbed at both Index and Squamish).

One source of this inconsistency is the previous hardest grade of 5.9 or 5.9+. For a long time, there was no 5.10 grade in the Yosemite Decimal System, and routes that would have been given a grade of 5.10 or even 5.11 if established more recently were given a grade of 5.9+. It’s no wonder then that some of those 5.9 classics feel several grades harder.

Sport and trad climbing grades

Climbers from different countries have different grading systems for the same reason that people native to different countries drive on different sides of the road and use different standards of measurement – everybody thinks their way is better. And so, while a single system would make more sense, we have a dozen different grading systems to contend with. Here are the four most common ones.


The Yosemite Decimal System consists of five general classes, but only the fifth is used for grading climbing routes. The four easier classes describe everything from a walk on flat ground (Class 1) to a technical scramble (Class 4). Everything harder than that (what most people would want to rope up for) is given a decimal grade according to the difficulty of the crux move in that route. But the American grading system doesn’t end there.

YDS classes

In addition to the YDS grade, modern American trad climbs are also given a gear rating. These ‘film’ ratings start with F for family, which are reserved for safe, well protected climbs, then proceed to PG or parental guidance, which warns you that gear may be tricky or runout, and then R ‘restricted’ which means you’d probably injure yourself if you fell. At the very end of the ‘Oh shit!’ spectrum is X, where a fall can result in serious injury or death.

YDS gear grades

The BMC system

The system used for grading trad routes in Britain actually involves the combination of two grades: the adjectival grade, which gives a sense of the overall difficulty of a route (taking into account strenuousness, exposure, seriousness, rock quality and other factors); and the technical grade, which indicates the difficulty of the hardest move on a route, irrespective of how many of them there are.

Adjectival grade

According to this system M is moderate, D is Hard Difficult, and VD is Very Difficult, though these names might seem like misnomers in this day and age. HVS (Hard Very Severe) which is five grades harder is still only the equivalent of 5.10a, but this then continues into the E’s (Extreme) the upper limits of which denote a grade better left to hard men and women.

Technical grade

The adjectival grade tells only half the story. If you want to know how physical and technical the actual moves will be, you have to look at the technical grade. This scale starts at 4a and proceeds much like the French grading system (described below) but without the plus grades. 4a is followed by 4b, which is followed by 4c, which then ticks over to 5a. This continues up until 7b, a level of difficulty only ever seen on E7 to E10.

BMC grade example

The French system

The system developed by the French for sport climbing is used not only in France but also in Britain on bolted routes, and in parts of Asia. Here, grades work in a similar way to the YDS in that number grades are split by letters. The difference is that with the YDS they have a, b, c and d on top of the number grade, but in the French system, each a, b, and c grade is split again by adding a plus symbol to the harder of the two grades.

It’s also important to note that French bouldering grades (Font grades) are written in a way very similar to French sport grades. The only difference is that bouldering grades are written with higher case letters and not lower case letters, as is used with the French sport grades. And if you’re wondering why I haven’t mentioned bouldering grades up until now, it’s because they don’t translate smoothly into sport grades. I’ve given them their own chart.

The UIAA system

This is the system of Roman numerals commonly used to grade sport routes in Germany, Italy, and parts of Eastern Europe. Like the French system, the UIAA makes use of a plus symbol to designate a harder grade, but, unlike any other system, it also includes a minus symbol for the easier of three grades in the same number. At the low end of the scale, you will find III (5.4), while the upper limit ends with XI (5.15).

climbing grades table

Bouldering grades

For some reason, there just aren’t as many grading systems for bouldering as there are for roped climbing. The upside to this, of course, is that converting grades is very simple. 

The V scale

The V scale was developed by pioneering American boulderer John Sherman. ‘Vermin’, as his friends called him, realized that a consistent system for grading boulder problems would help new climbers and veterans alike, and the V scale was first published in his guidebook to bouldering in Hueco Tanks. Since then it has gone on to become the standard for grading boulder problems in the U.S.

The Font scale

Outside the United States, the norm is to use the French standard, the ‘Font’ or Fontainebleau system. Much like the French sport climbing grading system, the Font scale designates grades using a numeral (3 to 9), a letter (A to C) and - or + symbol. In fact, the only difference between the two systems is that the sport grades are written with a lowercase letter, and the Font grades are written with a uppercase letter.

bouldering grades

Converting roped climbing grades to bouldering grades

Given the differences between the two styles, it’s difficult to convert roped climbing grades to bouldering grades. Some climbers compare the difficulty of a boulder problem graded 5 in the Font system to a 6b sport climb, but such a comparison fails to account for the differences in endurance and skills, like resting, needed in one and not the other.