base64 — base64 encode/decode data and print to standard output


base64 [OPTION...] [FILE]


Base64 encode or decode FILE, or standard input, to standard output.

Mandatory arguments to long options are mandatory for short options too.

−d, −−decode

decode data

−i, −−ignore−garbage

when decoding, ignore non−alphabet characters

−w, −−wrap=COLS

wrap encoded lines after COLS character (default 76). Use 0 to disable line wrapping


display this help and exit


output version information and exit

With no FILE, or when FILE is −, read standard input.

The data are encoded as described for the base64 alphabet in RFC 3548. When decoding, the input may contain newlines in addition to the bytes of the formal base64 alphabet. Use −−ignore−garbage to attempt to recover from any other non−alphabet bytes in the encoded stream.


Written by Simon Josefsson.


Report base64 bugs to bug−

GNU coreutils home page: <>

General help using GNU software: <>

Report base64 translation bugs to <>


The full documentation for base64 is maintained as a Texinfo manual. If the info and base64 programs are properly installed at your site, the command

  • info coreutils 'base64 invocation'

should give you access to the complete manual.


Copyright © 2013 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <>.

This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.