Are indoor and outdoor bouldering grades the same?
Indoor and outdoor bouldering use the same two systems, Font and V-Scale, but no fixed rule says an indoor grade matches the same grade outdoors. The BMC says grades can vary between walls and gives no offset between a wall and a crag. Checked 29 October 2026.
Same systems
The BMC says the grades at UK climbing walls are based on those used for outdoor bouldering and sport climbing. UK walls typically use Font or V-grades for bouldering.
Walls differ
Different walls sometimes use slightly different grading systems or variations on one. Asked whether grades vary between walls, the BMC answers: in short, yes, because grades are subjective to both the climber and the route setter and are hard to standardise.
The BMC pages we read do not say whether indoor grades run easier or harder than outdoor ones, so we do not either.
At the wall
Some walls group boulder problems into circuits, and a circuit can span two or three grades. Most walls have signage explaining their system, and the BMC says to ask a member of staff if you are not sure.
Source
- British Mountaineering Council, Indoor climbing grades explained: https://www.thebmc.co.uk/en/indoor-climbing-grades-explained
For all six grade systems side by side, see climbing grades explained.