FONT grades 1 to 5 should not have a,b,c suffixes

[Ugzuzg]

The Font-scale is an open-ended scale that starts at 1 and increases in single-digit steps but uses a "+" for additional refinement between steps; from grade 6 it introduces a capitalized "A", "B" and "C" for further refinement

/^((?:[1-5][+]?)|(?:[6-9][a-c][+]?))(?:(\/)((?:[1-5][+]?)|(?:[6-9][a-c][+]?)))?$/i

[vnugent]

Thanks for reporting this. Can you link a source that explains Font system in great detail?

[Ugzuzg]

I could only find a description on Wikipedia: https://en.wikipedia.org/wiki/Grade_(climbing)#Font_grade

On every other page they just post a comparison table like this:

http://www.northwalesbouldering.com/newsitem.asp?nsid=540
https://media.rockfax.com/pdfs/boulder_grade.pdf