The date time string is in the following format: 06/12/2012 07:21:22. How can I convert it to UNIX timestamp or epoch?

6 Answers

What you're looking for is date --date='06/12/2012 07:21:22' +"%s". Keep in mind that this assumes you're using GNU coreutils, as both --date and the %s format string are GNU extensions. POSIX doesn't specify either of those, so there is no portable way of making such conversion even on POSIX compliant systems.

Consult the appropriate manual page for other versions of date.

Note: bash --date and -d option expects the date in US or ISO8601 format, i.e. mm/dd/yyyy or yyyy-mm-dd, not in UK, EU, or any other format.

For Linux, run this command:

date -d '06/12/2012 07:21:22' +"%s" 

For macOS, run this command:

date -j -u -f "%a %b %d %T %Z %Y" "Tue Sep 28 19:35:15 EDT 2010" "+%s" 

A lot of these answers overly complicated and also missing how to use variables. This is how you would do it more simply on standard Linux system (as previously mentioned the date command would have to be adjusted for Mac Users) :

Sample script:

#!/bin/bash orig="Apr 28 07:50:01" epoch=$(date -d "${orig}" +"%s") epoch_to_date=$(date -d @$epoch +%Y%m%d_%H%M%S) echo "RESULTS:" echo "original = $orig" echo "epoch conv = $epoch" echo "epoch to human readable time stamp = $epoch_to_date" 

Results in :

RESULTS: original = Apr 28 07:50:01 epoch conv = 1524916201 epoch to human readable time stamp = 20180428_075001 

Or as a function :

# -- Converts from human to epoch or epoch to human, specifically "Apr 28 07:50:01" human. # typeset now=$(date +"%s") # typeset now_human_date=$(convert_cron_time "human" "$now") function convert_cron_time() { case "${1,,}" in epoch) # human to epoch (eg. "Apr 28 07:50:01" to 1524916201) echo $(date -d "${2}" +"%s") ;; human) # epoch to human (eg. 1524916201 to "Apr 28 07:50:01") echo $(date -d "@${2}" +"%b %d %H:%M:%S") ;; esac } 

Just be sure what timezone you want to use.

datetime="06/12/2012 07:21:22" 

Most popular use takes machine timezone.

date -d "$datetime" +"%s" #depends on local timezone, my output = "1339456882" 

But in case you intentionally want to pass UTC datetime and you want proper timezone you need to add -u flag. Otherwise you convert it from your local timezone.

date -u -d "$datetime" +"%s" #general output = "1339485682" 

Efficient way to convert date time string to epoch in bash

Avoiding useless repetitives forks, in order to make this translation a lot quicker...

Instead of running 1 fork for each translation, we could run date -f - +%s as background process...

Intro

Common syntax:

epochDate=$(date -d "$InputDate" +%s) 

Work fine, but become heavy if run repetetively!

In this post, you will find

• a Quick Demo, following this,
• some Explanations,
• a Function useable for many Un*x tools (bc, rot13, sed...).

Quick Demo

fifo=$HOME/.fifoDate-$$ mkfifo $fifo exec 5> >(exec stdbuf -o0 date -f - +%s >$fifo 2>&1) echo now 1>&5 exec 6< $fifo rm $fifo read -t 1 -u 6 now echo $now 

This must output current UNIXTIME. From there, you could compare

time for i in {1..5000};do echo >&5 "now" ; read -t 1 -u6 ans;done real 0m0.298s user 0m0.132s sys 0m0.096s 

and:

time for i in {1..5000};do ans=$(date +%s -d "now");done real 0m6.826s user 0m0.256s sys 0m1.364s 

From more than 6 seconds to less than a half second!!(on my host).

You could check echo $ans, replace "now" by "2019-25-12 20:10:00" and so on...

Optionaly, you could, once requirement of date subprocess ended:

exec 5>&- ; exec 6<&- 

Original post (detailed explanation)

Instead of running 1 fork by date to convert, run date just 1 time and do all convertion with same process (this could become a lot quicker)!:

date -f - +%s <<eof Apr 17 2014 May 21 2012 Mar 8 00:07 Feb 11 00:09 eof 1397685600 1337551200 1520464020 1518304140 

Sample:

start1=$(LANG=C ps ho lstart 1) start2=$(LANG=C ps ho lstart $$) dirchg=$(LANG=C date -r .) read -p "A date: " userdate { read start1 ; read start2 ; read dirchg ; read userdate ;} < <( date -f - +%s <<<"$start1"$'\n'"$start2"$'\n'"$dirchg"$'\n'"$userdate" ) 

Then now have a look:

declare -p start1 start2 dirchg userdate 

(may answer something like:

declare -- start1="1518549549" declare -- start2="1520183716" declare -- dirchg="1520601919" declare -- userdate="1397685600" 

This was done in one execution!

Using long running subprocess

We just need one fifo:

mkfifo /tmp/myDateFifo exec 7> >(exec stdbuf -o0 /bin/date -f - +%s >/tmp/myDateFifo) exec 8</tmp/myDateFifo rm /tmp/myDateFifo 

(Note: As process is running and all descriptors are opened, we could safely remove fifo's filesystem entry.)

Then now:

LANG=C ps ho lstart 1 $$ >&7 read -u 8 start1 read -u 8 start2 LANG=C date -r . >&7 read -u 8 dirchg read -p "Some date: " userdate echo >&7 $userdate read -u 8 userdate 

We could buid a little function:

mydate() { local var=$1; shift; echo >&7 $@ read -u 8 $var } mydate start1 $(LANG=C ps ho lstart 1) echo $start1 

Or use my newConnector function

With functions for connecting MySQL/MariaDB, PostgreSQL and SQLite...

You may find them in different version on GitHub, or on my site: download or show.

wget . shell_connector.bash newConnector /bin/date '-f - +%s' @0 0 myDate "2018-1-1 12:00" test echo $test 1514804400 

Nota: On GitHub, functions and test are separated files. On my site test are run simply if this script is not sourced.

# Exit here if script is sourced [ "$0" = "$BASH_SOURCE" ] || { true;return 0;} 

get_curr_date () { # get unix time DATE=$(date +%s) echo "DATE_CURR : "$DATE } conv_utime_hread () { # convert unix time to human readable format DATE_HREAD=$(date -d @$DATE +%Y%m%d_%H%M%S) echo "DATE_HREAD : "$DATE_HREAD }