Base64 Encoding

Some error messages

What is Base64 Encoding?

Base64 decoding is the process of converting a Base64-encoded string back into its original binary data. This process is essentially the reverse of the Base64 encoding process.

To decode a Base64-encoded string, the string is first parsed into groups of 4 characters. Each group of 4 characters corresponds to three 8-bit bytes of the original binary data. These three bytes are then combined into a single 24-bit value and split into four 6-bit values.

Each of these 6-bit values is then converted into its corresponding 8-bit value, resulting in a block of three bytes of the original binary data. This process is repeated for each group of 4 characters in the encoded string, until the entire string has been decoded.

If the original binary data was not a multiple of 3 bytes, padding characters (usually the "=" character) were added to the end of the encoded string to make the length a multiple of 4 characters. These padding characters are ignored during the decoding process.


  1. Base64 on Wikipedia