What is the noun for "committable"?

Solution 1:

This Google ngram suggests that both committability and commitability are used, with the former being preferred over the latter. Their usage appears to be quite rare and specialised. Initially, committability seems to have been used primarily in the field of psychiatry. Later years show its increasing usage in computer books as evidenced here.

Solution 2:

"Committable" was listed in the 1913 Webster's dictionary as an adjective. There's no reason to assume that the noun form of this word, "committability," meaning "the quality of being committable" or "suitability to be committed," is invalid or grammatically incorrect.

For comparison see "commutable" and "commutability."

Solution 3:

My first thought was to use "commissible"/"commissibility", which is also not a word. "Committable"/"commitability" sounds fine, though.