FASTBASE64(1)                    User Commands                   FASTBASE64(1)

NAME
       fastbase64 - base64 encode/decode data and print to standard output

SYNOPSIS
       fastbase64 [-Ddh] [-b num] [-i in_file] [-o out_file]

DESCRIPTION
       fastbase64 encodes or decodes base64 data using the high-performance
       simdutf library.  By default, it encodes binary input to base64 output.
       On large files, it can be several times faster than standard base64
       tools.  If a second filename is provided, it is used as the output
       file.  Otherwise, output goes to standard output.

OPTIONS
       -b, --break num
              break encoded output up into lines of length num (default 0,
              meaning no breaks)

       -D, -d, --decode
              decode input

       -h, --help
              display this message

       -i, --input in_file
              input file (default: "-" for stdin)

       -o, --output out_file
              output file (default: "-" for stdout)

       -w, --wrap=NUM
              same as -b

       -e, --encode
              encode input (default)

       --ignore-garbage
              when decoding, ignore non-alphabet characters

       --version
              output version information and exit

EXAMPLES
       Encode a file (default, no wrapping):
              fastbase64 -i myfile.txt

       Decode base64 data:
              fastbase64 -d -i encoded.txt

       Encode with custom line wrapping:
              fastbase64 -b 76 -i myfile.txt

SEE ALSO
       base64(1), fastbase64.coreutils(1), iconv(1)

AUTHOR
       Written by the simdutf development team.

simdutf                           March 2026                     FASTBASE64(1)