Base64 Encode

Definition

Base64 encoding is a binary-to-text encoding scheme that represents binary data in an ASCII string format. This is commonly used for sending and storing binary data over text-based channels such as email, chat messages, or web pages. The encoding process takes three 8-bit binary bytes and converts them into four 6-bit values. These 6-bit values are then represented as a character in the Base64 character set.

The Base64 character set consists of 64 characters, including uppercase and lowercase letters, numbers, and two additional characters that vary depending on the implementation. The encoding process takes groups of three bytes and converts them into a string of four characters from the Base64 set. If the input is not an exact multiple of three bytes, the data is padded with "=" characters until it is.

The encoded data is larger than the original binary data since three bytes of data become four bytes of Base64-encoded data. This increase in size is known as the encoding overhead. Despite the increased size, Base64 encoding is often used in situations where binary data needs to be transmitted or stored as text, such as when sending images as email attachments or embedding images in HTML documents.

To decode Base64 data, the encoded string is converted back into its original binary form using a decoding algorithm. The algorithm reads the input Base64-encoded string in groups of four characters and converts them back into three bytes of binary data. If the input string is padded with "=" characters, they are removed during the decoding process.

In summary, Base64 encoding is a widely used binary-to-text encoding scheme that allows for the secure transmission and storage of binary data in a text format. It is commonly used in applications such as email, web pages, and HTML documents.