Base64 Encoder/Decoder
A simple tool for encoding and decoding Base64 strings
About Base64 Encoding
The standard for binary-to-text encoding since 1993
What is it?
Base64 is a binary-to-text encoding scheme that represents binary data in an ASCII string format. It was originally designed to allow binary data to be transmitted over channels that were designed to handle only textual data, ensuring that the data remains intact without modification during transport.
How It Works
Base64 encoding converts every 3 bytes (24 bits) of binary data into 4 ASCII characters. It uses a set of 64 characters: A-Z, a-z, 0-9, +, and /. When the input length isn't a multiple of 3, padding characters (=) are added to the end.
Common Uses
- Email Attachments: MIME email protocol uses Base64 to encode binary attachments
- Data URIs: Embedding images and other files directly in HTML/CSS
- Web APIs: Transmitting binary data in JSON or XML
- Basic Authentication: HTTP Basic Authentication credentials
- Cryptography: Representing encrypted data or cryptographic keys
History
Base64 encoding was first defined in RFC 1421 (1993) as part of the Privacy Enhancement for Internet Electronic Mail (PEM) specification. It has since become a fundamental encoding scheme in web development and data transmission, with variations defined in RFC 2045 (MIME) and RFC 4648 (the current standard).
Security Notice
Base64 is an encoding method, not encryption. It does not provide any security or privacy. Anyone can decode Base64-encoded data back to its original form. Never use Base64 alone to protect sensitive information.