I have learned how to Base16 encode a string in PHP, but how do I Base36 encode and decode a string in PHP?
Note I need this to make the string work in URLs.
BONUS: And if you know how to compress the string slightly first before doing the Base36, that would be even cooler! :)
Google told me this: http://darklaunch.com/2009/07/31/base36-encode-and-decode-using-php-with-example-base36-encode-base36-decode
Anyway, base64 should fit your needs if you want to use it inside an URL.
Bonus: gzcompress() and gzuncompress() ;) (Zlib extension must be installed).