Base64 Encoder and Decoder

Where Base64 turns up

• Inline images in HTML or CSS. Writing a small icon as a data:image/png;base64,… URI saves the browser one HTTP request.
• Basic authentication. The header reads Authorization: Basic, followed by "user:password" written in Base64.
• JWTs and API tokens. The payload of a JWT is encoded as URL-safe Base64.
• Binary data in JSON or a database. Useful when a field will only accept plain text.
• Email attachments. SMTP carries attached files in MIME encoding.

Keep in mind that Base64 only changes how data is written. It is not encryption, anyone can reverse it, and it should never be used to protect a secret.