Hi, @matt-long, @coises and All,
Of course, the @coises’s plugin would be the best solution, being both flexible and powerful
However, @matt-long, if you don’t want to install any new plugin, here is a solution with native N++ only !
Of course, I’ll use the part of file which ONLY needs changes. But, in your personal file, the trailing part of each line will stay unchanged !
So, let’s suppose an INPUT text, like below, pasted in a new tab :
09-Jan-26 00:00:00 AM,
13-Sep-21 02:00:59 AM,
13-Jul-24 04:57:29 AM,
19-Apr-20 07:42:50 AM,
01-Mar-26 09:12:43 AM,
29-Feb-24 11:08:51 AM,
25-Jul-23 11:59:59 AM,
09-Jan-19 12:00:00 AM,
01-May-26 00:00:00 PM,
08-Oct-25 02:54:31 PM,
17-Feb-22 03:29:35 PM,
23-Sep-18 06:37:06 PM,
03-Nov-20 08:55:44 PM,
31-Aug-26 10:38:00 PM,
31-Dec-20 11:59:59 PM,
01-May-26 12:00:00 PM,
Open the Replace dialog
Uncheck all box options
FIND (?-si)^(0(\d)|\d\d)-(.+?)-(\d\d) (\d\d):(\d\d):\d\d (AM|PM)(?=,)
REPLACE (?2\2:\1)/\3/(?{4}20\4) \5\7:\6
Check the Wrap around option
Select the Regular expression search mode
Click on the Replace All button
=> You should obtain the temporary OUTPUT text below :
9/Jan/2026 00AM:00,
13/Sep/2021 02AM:00,
13/Jul/2024 04AM:57,
19/Apr/2020 07AM:42,
1/Mar/2026 09AM:12,
29/Feb/2024 11AM:08,
25/Jul/2023 11AM:59,
9/Jan/2019 12AM:00,
1/May/2026 00PM:00,
8/Oct/2025 02PM:54,
17/Feb/2022 03PM:29,
23/Sep/2018 06PM:37,
3/Nov/2020 08PM:55,
31/Aug/2026 10PM:38,
31/Dec/2020 11PM:59,
1/May/2026 12PM:00,
Now, APPEND at the very end of your file, all the lines below :
#Jan 1
#Feb 2
#Mar 3
#Apr 4
#May 5
#Jun 6
#Jul 7
#Aug 8
#Sep 9
#Sept 9
#Oct 10
#Nov 11
#Dec 12
#00AM 00
#01AM 01
#02AM 02
#03AM 03
#04AM 04
#05AM 05
#06AM 06
#07AM 07
#08AM 08
#09AM 09
#10AM 10
#11AM 11
#12AM 12
#00PM 12
#01PM 13
#02PM 14
#03PM 15
#04PM 16
#05PM 17
#06PM 18
#07PM 19
#08PM 20
#09PM 21
#10PM 22
#11PM 23
#12PM 00
Thus, your INPUT text is now as below :
9/Jan/2026 00AM:00,
13/Sep/2021 02AM:00,
13/Jul/2024 04AM:57,
19/Apr/2020 07AM:42,
1/Mar/2026 09AM:12,
29/Feb/2024 11AM:08,
25/Jul/2023 11AM:59,
9/Jan/2019 12AM:00,
1/May/2026 00PM:00,
8/Oct/2025 02PM:54,
17/Feb/2022 03PM:29,
23/Sep/2018 06PM:37,
3/Nov/2020 08PM:55,
31/Aug/2026 10PM:38,
31/Dec/2020 11PM:59,
1/May/2026 12PM:00,
#Jan 1
#Feb 2
#Mar 3
#Apr 4
#May 5
#Jun 6
#Jul 7
#Aug 8
#Sep 9
#Sept 9
#Oct 10
#Nov 11
#Dec 12
#00AM 00
#01AM 01
#02AM 02
#03AM 03
#04AM 04
#05AM 05
#06AM 06
#07AM 07
#08AM 08
#09AM 09
#10AM 10
#11AM 11
#12AM 12
#00PM 12
#01PM 13
#02PM 14
#03PM 15
#04PM 16
#05PM 17
#06PM 18
#07PM 19
#08PM 20
#09PM 21
#10PM 22
#11PM 23
#12PM 00
Open again the Replace dialog
Uncheck all box options
FIND (?-si)(?|(\u\l\l|Sept)|(\d\d(?:AM|PM)))(?=(?s).+^#\1 (\d+))|(?s)^#.+
REPLACE \2
Check the Wrap around option
Select the Regular expression search mode
Click on the Replace All button
=> You should get your expected OUTPUT text :
9/1/2026 00:00,
13/9/2021 02:00,
13/7/2024 04:57,
19/4/2020 07:42,
1/3/2026 09:12,
29/2/2024 11:08,
25/7/2023 11:59,
9/1/2019 12:00,
1/5/2026 12:00,
8/10/2025 14:54,
17/2/2022 15:29,
23/9/2018 18:37,
3/11/2020 20:55,
31/8/2026 22:38,
31/12/2020 23:59,
1/5/2026 00:00,
Voila !
Best Regards,
guy038