The Base64 online decoding tool provides Base64 encoding, Base64 online decoding, Base64 encryption and decryption, encrypting strings in Base64 format, and decrypting encoded Base64 back to plaintext. Base64 is a relatively common online encryption algorithm. When dealing with Chinese garbled characters, encoding Chinese in different ways can effectively avoid garbled characters. This site does not record any of your information, please feel free to use it.
Base64 encoding uses 64 printable ASCII characters (A-Z, a-z, 0-9, +, /) to encode arbitrary byte sequence data into ASCII strings, with the \"=\" symbol used as padding.
| Value | Character | Value | Character | Value | Character | Value | Character |
| 0 | A | 16 | Q | 32 | g | 48 | w |
| 1 | B | 17 | R | 33 | h | 49 | x |
| 2 | C | 18 | S | 34 | i | 50 | y |
| 3 | D | 19 | T | 35 | j | 51 | z |
| 4 | E | 20 | U | 36 | k | 52 | 0 |
| 5 | F | 21 | V | 37 | l | 53 | 1 |
| 6 | G | 22 | W | 38 | m | 54 | 2 |
| 7 | H | 23 | X | 39 | n | 55 | 3 |
| 8 | I | 24 | Y | 40 | o | 56 | 4 |
| 9 | J | 25 | Z | 41 | p | 57 | 5 |
| 10 | K | 26 | a | 42 | q | 58 | 6 |
| 11 | L | 27 | b | 43 | r | 59 | 7 |
| 12 | M | 28 | c | 44 | s | 60 | 8 |
| 13 | N | 29 | d | 45 | t | 61 | 9 |
| 14 | O | 30 | e | 46 | u | 62 | + |
| 15 | P | 31 | f | 47 | v | 63 | / |
Base64 splits the input string into bytes, obtains the binary value of each byte (padding with zeros to 8 bits if necessary), concatenates these binary values, then splits them into groups of 6 bits (since 2^6=64). If the last group has less than 6 bits, zeros are added at the end. Each group of 6 bits is converted to a decimal value, and the corresponding symbol is found in the table above. Concatenating these symbols yields the Base64 encoded result.
Base64 can be used for low-level binary data encoding of arbitrary data, for use in situations where only ASCII characters can be transmitted. However, it is most commonly used for text data processing and transmission. For example, in MIME format emails, Base64 can be used to encode email content for transmission between computers in different languages without garbled characters. Note that it is for transmission, not display. For example, using UTF-8 encoding on computers in Western Europe can display Chinese normally (if the corresponding font is installed), but it may not transmit Chinese correctly. Converting to Base64 eliminates this concern.
Unless otherwise specified, Base64 encoding typically handles non-ASCII characters according to the UTF-8 character set.