SlimTweet tries to shorten a message by applying a set of rules. For example,
and will be replaced by
it is will be replaced by
Substitutions will be made one at a time until the message reaches a target length (140 characters by default).
If SlimTweet still can't make the message fit, it will start tweaking the Unicode characters which make up your message, without changing its appearance too much. For example, the digraph
vi will be replaced by the roman numeral character
ⅵ. When rendered in a standard font, these substitutions are nearly inⅵsible.