Have never gone bouldering.
How does the grading work?

In simple terms, the effort to do a 6a boulder problem = the effort to do the crux on a 7a route - ie roughly one number grade apart (6b BP = 7b route etc).

Boulder grades are for a person of average height doing the problem with the correct beta (easiest sequence) in good conditions. Whereas route grades are for a person of average height doing the route onsight in good conditions.

The consequence of this is that a very technical boulder problem will feel super hard for the grade (until you work out the beta) - likewise a technical route will feel very easy to redpoint.

Hope this helps...

_________________
There's no point being pessimistic, because it probably won't work

I'd say not to worry too much about grades (difficult I know) when starting bouldering as it can be a little frustrating in the beginning. Rather find a few lines in your range that attract you in some way, and focus on learning more about moving on rock and what is possible?!

Guy, now you are taking a bit of long shot. Bouldering grades are most definitely not that far off sport grades. What you are saying is that if i can boulder 6c i should be able to sport climb 7c??(29). Not a chance. 2 Grades harder at the most.

I believe what Guy is saying is that if you can boulder 6C you should be able to do the crux of a 7c route, not the whole route.

Hi Jean

I said that if you can boulder 6b, then you can do the crux of a 7b route (not necessarily do the route).

As you move up the grades, the two systems start to converge - the one number grade is just a rough guide. It's certainly true at boulder grade 6a (I actually think that the gap is bigger below that). Obviously long enduro routes are irrelevant.

Here's my guess of the boulder grade of the cruxes of a couple of routes:

Ward's Walkup 19/6a+ = grade 4 BP
Puffadder 22/6b+ = grade 5 BP
Red Guitar 25/7a+ = 6a+ BP (remember the BP grade assumes you know the sequence)
Bolero 26/7b = 6b+ BP
Point Break 29/7c+ = 6c BP (a bit skewed by endurance)
Cool like That 29/7c+ = 6c+

Obviously someone is going to argue over some of these being a bit out, ie something is 6a+ and not 6a or 6b - and they are probably right.

Remember one last thing - the route/problem is more important than the grade.

_________________
There's no point being pessimistic, because it probably won't work

i agree with guy's grade approximation, it's probably the best comparision i've heard, definately in the harder grades at least. but scott's point is even more relevant when starting out- look at the line, not the grade.

So where does the V grade fit in?
Maybe I should stick to trad. Much simpler. Even has pictures and all.

Two articles you might find interesting

http://www.8a.nu/eng/articles/gradjmf.shtml (Grading scales for routes and bouldering)
http://www.8a.nu/eng/articles/einstein.shtml

Brilliant.
Exactly what I need.
Shot for the links and advice….now to find a boulderpad.