The maximum Tweet length is 280 characters.
We need to allow 58 characters for the URL link, this leaves 222 characters (including spaces) which can be customized as a pre-set Tweet.
If you choose to white label the domain and URL of the shared asset or link these numbers will vary depending on the length of the new link.
Note: The user is able to edit or remove this pre-populated Tweet prior to posting.
Facebook
The maximum length for a Facebook Share is 51 Characters for the Title (the group name) and 60 Characters for the caption (the group description).
The maximum length for a LinkedIn Share is 177 characters.