decode base64: invalid input

Question

Trying to decode base64 file on GNU/Linux, I get \"base64: invalid input\".

$ base64 test.zip | base64 -d > test2.zip
base64: invalid input
$ ll test*
-rw-r--         


        

Answer 1

You can also try using

echo -n

to suppress new lines and padding the input length to a multiple of 4 with one to three equal characters

=

Answer 2

That version will not decode (by default) lines with separators, yet the encoder does that by default. (Newer versions don't have this problem.)

One solution:

base64 -w 0 foo.zip | base64 -d > foo2.zip

Alternate:

base64 foo.zip | base64 -di > foo2.zip

The -i option stands for (from the man page):

-i, --ignore-garbage
       When decoding, ignore non-alphabet characters.
[...]
Decoding require compliant input by default, use --ignore-garbage to
attempt to recover from non-alphabet characters (such as newlines)

Answer 3

If you're doing this on a mac, your version of base64 might not have the flexibility to handle ignoring garbage. If you brew install coreutils, you'll have the gbase64 utility and use it as Joe has described.

Answer 4

Or even more simply

base64 -di foo.zip > foo2.zip