TS(1) TS(1)

# [NAME](#NAME)

ts - timestamp input

# [SYNOPSIS](#SYNOPSIS)

ts \[-r] \[-i | -s] \[-m] \[format]

# [DESCRIPTION](#DESCRIPTION)

ts adds a timestamp to the beginning of each line of input.

The optional format parameter controls how the timestamp is formatted, as used by [**strftime**(3)](/man/enterprise-packages/moreutils/strftime.3). The default format is "%b %d %H:%M:%S". In addition to the regular strftime conversion specifications, "%.S" and "%.s" and "%.T" are like "%S" and "%s" and "%T", but provide subsecond resolution (ie, "30.00001" and "1301682593.00001" and "1:15:30.00001").

If the -r switch is passed, it instead converts existing timestamps in the input to relative times, such as "15m5s ago". Many common timestamp formats are supported. Note that the Time::Duration and Date::Parse perl modules are required for this mode to work. Currently, converting localized dates is not supported.

If both -r and a format is passed, the existing timestamps are converted to the specified format.

If the -i or -s switch is passed, ts reports incremental timestamps instead of absolute ones. The default format changes to "%H:%M:%S", and "%.S" and "%.s" can be used as well. In case of -i, every timestamp will be the time elapsed since the last timestamp. In case of -s, the time elapsed since start of the program is used.

The -m switch makes the system's monotonic clock be used.

# [ENVIRONMENT](#ENVIRONMENT)

The standard TZ environment variable controls what time zone dates are assumed to be in, if a timezone is not specified as part of the date.

# [AUTHOR](#AUTHOR)

Copyright 2006 by Joey Hess <id@joeyh.name>

Licensed under the GNU GPL.

2026-08-30 moreutils

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Document: ts(1) from moreutils 0.70-r1 (Chainguard OS)
Source: git://git.joeyh.name/moreutils