Manual: gnunumfmt

NUMFMT(1)						User Commands						   NUMFMT(1)

NAME
       numfmt - Convert numbers from/to human-readable strings

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

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

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

       --debug
	      print warnings about invalid input

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

       --field=FIELDS
	      replace the numbers in these input fields (default=1); see FIELDS below

       --format=FORMAT
	      use printf style floating-point FORMAT; see FORMAT below for details

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

       --from-unit=N
	      specify the input unit size (instead of the default 1)

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

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

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

       --padding=N
	      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

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

       --suffix=SUFFIX
	      add SUFFIX to output numbers, and accept optional SUFFIX in input numbers

       --to=UNIT
	      auto-scale output numbers to UNITs; see UNIT below

       --to-unit=N
	      the output unit size (instead of the default 1)

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

       --help display this help and exit

       --version
	      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, 1k = 1000, 1Ki = 1024, 1M = 1000000, 1Mi = 1048576,

       si     accept optional single letter suffix: 1k = 1000, 1K = 1000, 1M = 1000000, ...

       iec    accept optional single letter suffix: 1K = 1024, 1k = 1024, 1M = 1048576, ...

       iec-i  accept optional two-letter suffix: 1Ki = 1024, 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 conver‐
       sion  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  --in‐
       valid='ignore' conversion errors are not diagnosed and the exit status is 0.

EXAMPLES
	      $ 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

AUTHOR
       Written by Assaf Gordon.

REPORTING BUGS
       GNU coreutils online help: 
       Report any translation bugs to 

SEE ALSO
       Full documentation 
       or available locally via: info '(coreutils) numfmt invocation'

       Packaged by Ubuntu (9.7-3ubuntu2)
       Copyright © 2025 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.

GNU coreutils 9.7					January 2026						   NUMFMT(1)