Base64 Encode / Decode
Encode text to Base64 or decode Base64 back to text. Useful for emails, embedded data, and inspecting tokens. Uses native browser btoa/atob.
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About Base64 Encode / Decode
What is Base64?
A text encoding that uses 64 ASCII characters (A-Z, a-z, 0-9, +, /, with = padding) to represent arbitrary binary data. Designed in the 1980s for email attachments โ keeps binary safe through text-only channels.
Size cost
Base64 increases data size by ~33% (every 3 bytes becomes 4 ASCII characters). Why your email attachments are bigger than the source files; why embedded data URIs grow images.
Not encryption
Base64 is encoding, not encryption โ anyone can decode it instantly. Donโt use it to "hide" passwords or secrets. Itโs just a binary-to-text wrapper.