Base64 Encoder and Decoder

Convert text to Base64 (commonly used in data URIs, JWT, basic auth headers) and decode it back. Works correctly with emoji and any UTF-8 character. The URL-safe variant uses - and _ instead of + and / so the output is safe for URL params. Pair it with the URL Encoder when the value goes into a query string, with the JWT Decoder to inspect a token's payload, or with the SHA Hash Generator to fingerprint the bytes.