What is Base64?
Base64 encodes binary data using 64 printable characters (A–Z, a–z, 0–9, +, /). It is used to embed images in HTML/CSS (data URIs), send attachments in email, store binary values in JSON, and in HTTP Basic authentication.
Base64URL is a variant that uses - and _ instead of + and / and usually drops the = padding, so it is safe in URLs and file names. JSON Web Tokens use Base64URL.
How to use
- Choose Encode or Decode.
- Type or paste your text. The result updates instantly.
- To convert a file, use File → Base64; tick data URI to get a ready-to-paste
data:URL.
The decoder accepts both alphabets automatically, ignores whitespace and line breaks, and adds missing padding for you. Text is handled as UTF-8, so emoji and non-Latin scripts round-trip correctly.
Base64 is an encoding, not encryption. Anyone can decode it.