Tool to decrypt/encrypt with base 64. Base64 is a coding system using 64 characters, selected to be compatible with a majority of coding tables. It is used with emails for example.
Base64 Coding - dCode
Tag(s) : Character Encoding, Internet
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Base 64 Coding starts by splitting the binary code in groups of 6 bits, filling it with 0 if needed.
Example: Split as 011001 000100 001101 101111 011001 000110 0101 (+00)
Each group of 6 bits has a base 10 value, it corresponds to a character in the Base 64 alphabet (start at 0): ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/
Example: The conversion from 011001 to base 10 is 25 and in the alphabet 25 is Z, 000100 is 4, etc. to obtain the characters numbered 25 4 13 47 25 6 20 or the coded message: ZENvZGU
Base 64 only works with groups of 4 characters, if needed, fill with =.
Example: Finally ZENvZGU (that had 7 chars) becomes ZENvZGU= (8 chars, a multiple of 4) which is the final base64 encoded message.
Decryption consists in finding back values of the letters in the Base64 alphabet: ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/ (equal sign = is ignored)
Example: A coded message is YjY0, corresponding values of Y,j,Y,0 in the alphabet are: 24,35,24,52
Values are converted to 6-bit binary.
Example: 24 is converted 011000, 35 = 100011, etc. the decoded binary message is 011000100011011000110100
Example: In ASCII, 01100010,00110110,00110100 corresponds to the plain text b,6,4
The message is theoretically composed of a number of characters multiple of 4. To this end, the presence of characters = (equal) at the end of the message is a big clue.
The message has a maximum of 65 distinct characters (and possibly space or line break). By default it is: ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=
Base64 is typically used in emails for non-ASCII messages and attachments (via the MIME standard: Multipurpose Internet Mail Extensions)
The Usenet network used Base64 to transfer files, any indication referring to it is a clue.
Several signatures of users or sites are associated with Base64 as code 6.0 (94/25) or the .b64 extensions
Base64 is sometimes used to store passwords that cannot be encrypted, in order to prevent them from being displayed in plain text, as in the XML configuration files of certain software (Databases, FTP, Filezilla, etc.)
A Base64 encoded message will only contain printable ASCII characters ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=
This property allows transmitting any data on systems originally designed to transmit only text (without having to worry about the initial encoding or how the characters will appear on the screen of the recipient of the message)
No, as indicated in the encoding principle, the presence of characters = (equal) is not mandatory, it occurs approximately 3 times out of 4.
In Base64, 4 ASCII characters are used to code 3 bytes. Volume is increased by 33%.
Example: Base64 (6 characters) is coded QmFzZTY0 (8 characters or +33%)
base64 (no uppercase) is coded YmFzZTY0
The base64 uses a sixty-four character alphabet to code any binary string (in base 2), so it is a mathematical conversion to base 64.
Base64URL is a variant of Base64 suitable for URLs (http). Characters 62 + and 63 / can cause problems with URL, they can be replaced by respectively - and _. Furthermore, the equal = sign is deleted.
RFC 2045 norm officialising Base64 is from 1996