Climbing grade converter

Why there are so many scales

Climbing grades grew up regionally, long before anyone wanted to compare them. The UIAA scale comes from the Alps, the French scale from sport climbing, the Yosemite Decimal System from the United States. In bouldering the Fontainebleau scale was added, from the forest of the same name south of Paris, and the V scale from Hueco Tanks in Texas.

Because the systems grew independently of each other, they cannot be translated into one another exactly. Comparison tables are a tool for approximation, not an exchange rate.

The most common mix-up: 7A and 7a

Fontainebleau and the French sport climbing scale use the same numbers and letters and differ only in capitalisation. Font writes boulder grades in capitals — 6A, 7A, 8A. The sport climbing scale uses lower case — 6a, 7a, 8a. To force the distinction, Font is occasionally prefixed with a capital F and the sport scale with a lower-case f: F7A versus f7a.

The difference is substantial. According to the reference table, Font 7A sits at around 7b+ in sport climbing. Anyone who throws both scales into one table is systematically out by more than two grades. This calculator therefore does not allow the mix-up in the first place.

Comparison table for bouldering

Empty cells mean the V scale has no step of its own at that point — below 7C, Fontainebleau is more finely graded.

Comparison table for roped climbing

The UIAA scale is given in Roman numerals, as the UIAA and the German Alpine Club use them; next to it stands the Arabic notation displayed in many gyms.

Every conversion is an approximation. Depending on the source they differ by up to a full grade.

Frequently asked questions

Is Font 7A the same as French 7a?

No, and this is the most common mix-up. Fontainebleau writes boulder grades with a capital letter, the French sport climbing scale uses lower case. According to the reference table, Font 7A corresponds to roughly 7b+ in sport climbing — a difference of more than two grades. That is why this calculator separates bouldering and roped climbing and allows no conversion between the two.

Why does a range appear instead of a value for some grades?

Because the scales are divided into steps of different sizes. Between Font 6A and 6B there is still 6A+, whereas the V scale has no intermediate step at that point. Rather than rounding to the neighbouring value, the calculator shows both neighbours. Faking a precision the scale does not offer would be the worse solution.

How accurate are conversions between scales anyway?

They are approximations. Different sources differ by up to a full grade, and the same grade feels different on different rock and in different gyms. Among the bouldering scales, Fontainebleau and the V scale only match exactly from V9 or 7C upwards according to the sources used here; below that Fontainebleau is more finely graded.

Why is UIAA written in Roman numerals here?

Because the UIAA and the German Alpine Club do it that way: VI, VII−, VIII+. Gyms often display the Arabic notation with the same steps: 6, 7−, 8+. Both mean the same thing, so the calculator shows both notations.

Are gym grades and rock grades comparable?

Only to a limited extent. Boulders in the gym are considered to be graded more softly than outdoors up to about V10 or Font 7C+. From that range upwards most climbers have outdoor experience anyway, which makes the difference disappear.

Related

The tables say which grade matches which — but not where the scales come from and why they differ in the first place. That is covered by the articles in the knowledge hub.