# Filename numbers
**URL:** https://community.mp3tag.de/t/filename-numbers/4499
**Category:** Support
**Created:** [February 21, 2007, 1:33pm UTC](https://community.mp3tag.de/t/filename-numbers/4499 "2007-02-21T13:33:41Z")
**Posts on this page:** 4
**Page:** 1
### Author:  [@percepto](https://community.mp3tag.de/u/percepto)
#### Post date: [February 21, 2007, 1:33pm UTC](https://community.mp3tag.de/t/filename-numbers/4499/1 "2007-02-21T13:33:41Z")
Hi,
I know it's probably on here somewhere but I can't find it! I have read a lot about regular expressions, so I imagine that my query is a very simple one.
I want to change the filenames from
1 - Trackname - Artist
to
01 - Trackname - Artist
I know I can Ctrl K and change the track tags and then go Tag-Filename,but this is a little pointless as the track tags don't need 2 digits.
Thanks in advance
percepto
---
### Author:  [@DetlevD](https://community.mp3tag.de/u/DetlevD)
#### Post date: [February 21, 2007, 2:02pm UTC](https://community.mp3tag.de/t/filename-numbers/4499/2 "2007-02-21T14:02:02Z")
> [@percepto](#):
>
> ... I want to change the filenames from '1 - Trackname - Artist' to '01 - Trackname - Artist' ...
This seems to work:
DD.20070221.1601
---
### Author:  [@percepto](https://community.mp3tag.de/u/percepto)
#### Post date: [February 21, 2007, 2:12pm UTC](https://community.mp3tag.de/t/filename-numbers/4499/3 "2007-02-21T14:12:59Z")
It certainly does!
Many thanks
percepto
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### Author:  [@system](https://community.mp3tag.de/u/system)
#### Post date: [February 9, 2026, 12:20pm UTC](https://community.mp3tag.de/t/filename-numbers/4499/4 "2026-02-09T12:20:10Z")