# Regex for missing title
**URL:** https://community.mp3tag.de/t/regex-for-missing-title/14147
**Category:** Support
**Created:** [November 19, 2012, 5:59pm UTC](https://community.mp3tag.de/t/regex-for-missing-title/14147 "2012-11-19T17:59:01Z")
**Posts on this page:** 7
**Page:** 1
### Author:  [@mitchind](https://community.mp3tag.de/u/mitchind)
#### Post date: [November 19, 2012, 5:59pm UTC](https://community.mp3tag.de/t/regex-for-missing-title/14147/1 "2012-11-19T17:59:01Z")
Newbie at this but have a lot working right now - just got stumped on MP3Tag's treatment of blank tags.
I have multiple files that display [Untitled] or [Untitled Track] for the %title% field.
I've tried to test using $strstr and $len - but $len seems to return the length as if it's filled in,
and $strstr doesn't seem to be able to find "Untitled" anywhere in the string.
I've read thru the regex FAQ but nothing seems to indicate how to handle the possibilities
I just want to replace any of these missing titles or titles starting with "[Untitled" with
"Untitled " + %track%
Is this has hard as I'm making it out to be?
Thanks for any help
Don
---
### Author:  [@stevehero](https://community.mp3tag.de/u/stevehero)
#### Post date: [November 19, 2012, 6:14pm UTC](https://community.mp3tag.de/t/regex-for-missing-title/14147/2 "2012-11-19T18:14:46Z")
> [@mitchind](#):
>
> I have multiple files that display [Untitled] or [Untitled Track] for the %title% field.
There's different ways of doing this but one is:
Begin Action Group **\_Script Test#TEST**
**Action #1** _Actiontype 5:_ **Format value** _Field \_\_\_\_\_\_:_ **TITLE** _Formatstring:_ **$regexp(%title%,'(?i)^\[untitled[^]]\*\]'$,$1 $num(%track%,2))**
End Action Group **\_Script Test#TEST** (1 Action)
It searches for the **%title%** to start with '**[**' then **untitled**. It then searches for anything but a '**]**' between 0 and an unlimited no. of times. Then a '**]**' This will match both:
**[Untitled]**
**[Untitled Track]**
And replace them with your desired format with the **%track%** formatted with 2 padded numbers.
See attached explanation of how regexp works.
---
### Author:  [@DetlevD](https://community.mp3tag.de/u/DetlevD)
#### Post date: [November 19, 2012, 6:18pm UTC](https://community.mp3tag.de/t/regex-for-missing-title/14147/3 "2012-11-19T18:18:56Z")
> [@mitchind](#):
>
> ... I have multiple files that display [Untitled] or [Untitled Track] for the %title% field. ...
> I just want to replace any of these missing titles or titles starting with "[Untitled" with
> "Untitled " + %track%
> ...
One possible approach ...
Converter: Tag - Tag
Field: TITLE
Format string: **$ifgreater($strstr(%TITLE%,'[Untitled'),0,'Untitled '%TRACK%,%TITLE%)**
DD.20121119.2015.CET
---
### Author:  [@mitchind](https://community.mp3tag.de/u/mitchind)
#### Post date: [November 19, 2012, 6:29pm UTC](https://community.mp3tag.de/t/regex-for-missing-title/14147/4 "2012-11-19T18:29:43Z")
Thanks for the quick reply - I'll give it a shot.
I assume I can try this from the Tag -\> filename rename window?
---
### Author:  [@stevehero](https://community.mp3tag.de/u/stevehero)
#### Post date: [November 19, 2012, 6:47pm UTC](https://community.mp3tag.de/t/regex-for-missing-title/14147/5 "2012-11-19T18:47:03Z")
Use 
---
### Author:  [@mitchind](https://community.mp3tag.de/u/mitchind)
#### Post date: [November 19, 2012, 6:47pm UTC](https://community.mp3tag.de/t/regex-for-missing-title/14147/6 "2012-11-19T18:47:19Z")
> [@DetlevD](#):
>
> One possible approach ...
> Converter: Tag - Tag
> Field: TITLE
> Format string: **$ifgreater($strstr(%TITLE%,'[Untitled'),0,'Untitled '%TRACK%,%TITLE%)**
>
> DD.20121119.2015.CET
That did it - thanks very much
---
### Author:  [@system](https://community.mp3tag.de/u/system)
#### Post date: [February 9, 2026, 12:24pm UTC](https://community.mp3tag.de/t/regex-for-missing-title/14147/7 "2026-02-09T12:24:11Z")