What is Base64?
Base64 is a binary-to-text encoding scheme that represents binary data in an ASCII string format. It is commonly used when binary data needs to be transmitted over media that is designed to handle text content. Base64 encoding increases the size of the data by approximately 33%.
Common Uses for Base64 Encoding
- Email Attachments: For encoding binary attachments in email systems
- Data URLs: Embedding images directly in HTML/CSS as data URLs
- Authentication: Encoding username and password in Basic Authentication
- APIs: Transmitting binary data in JSON or XML responses
- Cookies: Storing binary or complex data in HTTP cookies
- JWT Tokens: Encoding JSON data in authentication tokens
Base64 Encoding Features
- Character Set: Uses A-Z, a-z, 0-9, +, / and = (for padding)
- Padding: Uses = characters at the end to make the length a multiple of 4
- Non-Binary Characters: Produces output that uses only printable ASCII characters
- Reversible: Can be decoded back to the original data without any loss
- Size Increase: Encoded data is about 1.33 times the size of the original
Note: Base64 encoding is not a form of encryption or compression. It's merely a way to represent binary data in an ASCII string format.