Base64 Encoder/Decoder
Encode or decode Base64 text
Encode or decode Base64 text
Base64 writes any data with 64 safe characters (A–Z, a–z, 0–9, + and /) plus = as padding, so it survives channels built for text: data: URLs, Basic auth headers, JSON, email. Text is converted to UTF-8 first, so accents and emoji work. The output is about a third longer than the input. It is an encoding, not encryption.
Hello, World! → SGVsbG8sIFdvcmxkIQ==héllo wörld → aMOpbGxvIHfDtnJsZA==user:pass → dXNlcjpwYXNzNo. Base64 only changes how data is written; it has no key and anyone can decode it. Never use it to protect passwords or secrets.
Base64 encodes 3 bytes as 4 characters. When the input length is not a multiple of 3, the output is padded with one or two = signs.
Every 3 bytes become 4 characters, so the encoded data is about 33% larger.
A variant used in URLs and JWTs that replaces + with - and / with _ and usually omits the = padding.