numfmt - Convert numbers from/to human-readable strings


   numfmt [OPTION]... [NUMBER]...


   Reformat  NUMBER(s),  or  the  numbers  from standard input if none are

   Mandatory arguments to long options are  mandatory  for  short  options

          print warnings about invalid input

   -d, --delimiter=X
          use X instead of whitespace for field delimiter

          replace the numbers in these input fields (default=1) see FIELDS

          use printf style floating-point FORMAT;  see  FORMAT  below  for

          auto-scale  input  numbers to UNITs; default is 'none'; see UNIT

          specify the input unit size (instead of the default 1)

          use locale-defined grouping of  digits,  e.g.  1,000,000  (which
          means it has no effect in the C/POSIX locale)

          print  (without converting) the first N header lines; N defaults
          to 1 if not specified

          failure mode for invalid numbers: MODE can be: abort  (default),
          fail, warn, ignore

          pad  the  output  to  N characters; positive N will right-align;
          negative N will left-align; padding is ignored if the output  is
          wider  than  N;  the  default  is  to  automatically  pad  if  a
          whitespace is found

          use METHOD for rounding when scaling; METHOD can be:  up,  down,
          from-zero (default), towards-zero, nearest

          add  SUFFIX  to  output  numbers,  and accept optional SUFFIX in
          input numbers

          auto-scale output numbers to UNITs; see UNIT below

          the output unit size (instead of the default 1)

   -z, --zero-terminated
          line delimiter is NUL, not newline

   --help display this help and exit

          output version information and exit

   UNIT options:
   none   no auto-scaling is done; suffixes will trigger an error

   auto   accept optional single/two letter suffix:

          1K = 1000, 1Ki = 1024, 1M = 1000000, 1Mi = 1048576,

   si     accept optional single letter suffix:

          1K = 1000, 1M = 1000000, ...

   iec    accept optional single letter suffix:

          1K = 1024, 1M = 1048576, ...

   iec-i  accept optional two-letter suffix:

          1Ki = 1024, 1Mi = 1048576, ...

   FIELDS supports cut(1) style field ranges:
   N      N'th field, counted from 1

   N-     from N'th field, to end of line

   N-M    from N'th to M'th field (inclusive)

   -M     from first to M'th field (inclusive)

   -      all fields

   Multiple fields/ranges can be separated with commas

   FORMAT must be suitable for printing one floating-point argument  '%f'.
   Optional  quote  (%'f)  will enable --grouping (if supported by current
   locale).  Optional width value (%10f) will pad  output.  Optional  zero
   (%010f)  width  will  zero  pad  the  number.  Optional negative values
   (%-10f) will left align.  Optional precision (%.1f) will  override  the
   input determined precision.

   Exit  status is 0 if all input numbers were successfully converted.  By
   default, numfmt will stop at  the  first  conversion  error  with  exit
   status  2.   With  --invalid='fail'  a  warning  is  printed  for  each
   conversion error and the exit status is 2.  With --invalid='warn'  each
   conversion  error  is  diagnosed,  but  the  exit  status  is  0.  With
   --invalid='ignore' conversion errors are not  diagnosed  and  the  exit
   status is 0.


          $ numfmt --to=si 1000

          -> "1.0K"

          $ numfmt --to=iec 2048

          -> "2.0K"

          $ numfmt --to=iec-i 4096

          -> "4.0Ki"

          $ echo 1K | numfmt --from=si

          -> "1000"

          $ echo 1K | numfmt --from=iec

          -> "1024"

          $ df -B1 | numfmt --header --field 2-4 --to=si
          $ ls -l  | numfmt --header --field 5 --to=iec
          $ ls -lh | numfmt --header --field 5 --from=iec --padding=10
          $ ls -lh | numfmt --header --field 5 --from=iec --format %10f


   Written by Assaf Gordon.


   GNU coreutils online help: <>
   Report numfmt translation bugs to <>


   Copyright    2016  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.


   Full documentation at: <>
   or available locally via: info '(coreutils) numfmt invocation'


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