date¶

timestamp=$(date +%Y%m%dT%H%M%S%z)

Convert various formats to ISO-8601¶

$ echo "Sep 24 03:30:00 2023" | xargs -I {} date -d "{}" --iso-8601=seconds 2023-09-24T03:30:00+10:00

From epoch¶

$ date -d @1361234760
Tue Feb 19 11:46:00 2013

Replace all epoch timestamps in a file with Human Readable¶

$ echo foo,1361234760,bar | perl -pe 's/(\d+)/localtime($1)/e'
foo,Tue Feb 19 11:46:00 2013,bar