Base64 Encoder / Decoder

Base64 encodes binary data into a set of 64 printable ASCII characters (A-Z, a-z, 0-9, +, /). It's commonly used to embed binary data in text-based formats like JSON, XML, emails, and data URIs.

This tool uses a UTF-8 aware encoding approach: text is first encoded with encodeURIComponent, then processed with unescape, and finally Base64 encoded with btoa. This ensures non-ASCII characters (emoji, accented letters, CJK) are handled correctly.

Standard Base64 uses + and / which conflict with URL syntax. URL-safe Base64 replaces + with - and / with _, and optionally removes padding (=). This variant is used in JWTs, data URIs, and URL parameters.

MIME-compliant Base64 wraps output at 76 characters per line, as specified in RFC 2045. This is used in email attachments and certain legacy systems that require fixed-width line breaks.

Yes. All encoding and decoding happens locally in your browser — no data is sent to any server.