Base64 Encoding safe for filenames?

Question

Is Base64 encoding safe to use for filenames on Windows and Linux systems? From my research I have found that replacing all / characters of the result with

Answer 1

RFC 3548 suggests not only to replace the / character. The URL and Filename safe Alphabet replaces:

• the 63:nd / character with the underscore _
• the 62:nd + character with the minus -.

But maybe you better use a HEX-String. It is been a while, when i stored a hash value in a filename. I started with using Base64 String but switched to a Hex-String. I don't remember why i switched, maybe because Windows makes no difference between 'a' and 'A' as AndiDog said.