Hochreiter Software & IT Services
Home › Tools › Base64 En-/Decoder

Base64 En-/Decoder

Type on the left, get Base64 on the right - and the other way round. UTF-8 safe, URL-safe on demand. Runs entirely in your browser, nothing is transmitted.

Options

None of this matters when decoding - line breaks, missing padding and both alphabets are handled automatically.

Plain text

0 characters · 0 bytes

Base64

0 characters

In short

Base64 is not encryption, it is a transcription: arbitrary bytes are mapped onto 64 printable characters so they survive channels that only carry text (email, JSON, URLs, data URIs).

SizeEvery 3 bytes become 4 characters - encoded data is roughly a third larger than the original.
PaddingThe trailing = fill up the last group of four. Many systems (JWT, base64url) leave them out.
URL-safe+ and / get in the way inside URLs and file names. The base64url variant (RFC 4648 §5) replaces them with - and _.
Line breaksMIME (RFC 2045) wraps after 76 characters. Line breaks are ignored when decoding.
Not a secretAnyone can reverse Base64. Secrets need encryption, not encoding.
Copied