Climbing grades FAQ
Short answers to the questions people ask about climbing grades, built from the grade table in The Summit Social app and the British Mountaineering Council's grade pages. Each page names its source and was checked on 29 October 2026.
How hard is a 9c climb?
9c is the hardest grade proposed for a roped sport route so far: five routes carry it and none has been repeated, so none is confirmed.
How hard is a 5.9 climb?
A roped YDS grade, the last one before the letters start at 5.10; level 6 of 17 in the app's grade table.
Are indoor and outdoor bouldering grades the same?
They use the same systems, but no fixed rule links them: the BMC says walls differ and gives no offset between wall and crag.
What are bouldering grades?
Font (such as 6A or 7B+) and the V-Scale (such as V3 or V8) rate how hard a boulder problem is; the app logs either.
V grade to Font conversion
In the app's table V3 is Font 6A, V4 is 6B, V5 is 6C and V6 is 7A.
What does 6a mean in climbing?
French 6a is a roped sport route; a capital 6A is a Font boulder grade; 6a is also a British technical grade.
What is a UK trad grade?
Two parts: an adjectival grade like VS or E1 for overall difficulty, and a technical grade like 4c or 5b for the hardest move.
For all six grade systems side by side, see climbing grades explained.
Checked 29 October 2026.