Base64 Encoding

Definition

Base64 encoding converts binary data into a text format using 64 printable ASCII characters (A-Z, a-z, 0-9, +, /) plus = for padding. It is defined by IETF RFC 4648 and is commonly used for embedding images in HTML/CSS, encoding email attachments (MIME), storing binary data in JSON, and transmitting data in URL-safe formats. Base64 increases data size by approximately 33%. Base64URL is a variant that uses - and _ instead of + and / for URL safety.