Converting .rar files to .pdf format.
Converting WinRAR Compressed Archives directly to Adobe Portable Document Format (.rar to .pdf conversion) is not possible, at least as far as we know. Both file types are of completely different nature, and further have different functions.
A .rar archive could certainly contain one or more .pdf documents, which can be extracted by using WinRAR. A direct .rar to .pdf conversion is, however, very unlikely.
In a word, direct rar to pdf conversion is not possible.
So don't expect any so-called rar to pdf converter or rar to pdf free online conversion tool available.