Base64 encoder and decoder

Build Basic authentication headers, inspect encoded payloads and debug webhook signatures without leaking them to a server.

URL-safe alphabet (- and _, no padding)

Text to encode

VXB0aW1lTW9uaXRvcjM2MDogbW9uaXRvciB3aGF0IG1hdHRlcnMg4pyT

42 bytes in

UTF-8 is used for text. Base64 is an encoding, not encryption: anyone can decode it.

Monitor endpoints that require Basic authentication. Free for 5 monitors, no credit card.

How it measures

Text is encoded as UTF-8 before Base64; decoding is strict and reports invalid alphabets or lengths.
The URL-safe variant (RFC 4648 §5) replaces + and / with - and _ and drops padding.

Decoded data that is not valid UTF-8 is shown with replacement characters; download-style binary output is not offered.
Base64 is not encryption.

Invalid length error: Base64 comes in groups of four characters. A string with a length of 4n+1 cannot be valid; something was cut off.