# Replace with Reg Exp - not working on field with " \[ \] " **URL:** \ **Category:** Support\ **Created:** [February 13, 2015, 5:43pm UTC](https://community.mp3tag.de/t/replace-with-reg-exp-not-working-on-field-with/16596 "2015-02-13T17:43:17Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![DHoude](https://community.mp3tag.de/letter_avatar_proxy/v4/letter/d/74df32/32.png) [@DHoude](https://community.mp3tag.de/u/DHoude)\ **Post date:** [February 13, 2015, 5:43pm UTC](https://community.mp3tag.de/t/replace-with-reg-exp-not-working-on-field-with/16596/1 "2015-02-13T17:43:17Z")
Hello, I am trying to replace " [Single] " with " ". But the Replace with regular expression does not seem to be working on this item. I am using this on the TITLE field. I did mean to leave the spaces between the " "s. i just want it to find that and shorten it to 1 space. Is that possible? All my other Replace with Reg Exp actions seem to work fine. Any help is greatly appreciated, thank you ---
**Author:** ![ohrenkino](https://community.mp3tag.de/user_avatar/community.mp3tag.de/ohrenkino/32/4843_2.png) [@ohrenkino](https://community.mp3tag.de/u/ohrenkino)\ **Post date:** [February 13, 2015, 5:48pm UTC](https://community.mp3tag.de/t/replace-with-reg-exp-not-working-on-field-with/16596/2 "2015-02-13T17:48:06Z")
The square brackets describe a range in a regular expression, e.g. [a-z] for all lower case letters. see [https://docs.mp3tag.de/actions/replace-regexp](https://docs.mp3tag.de/actions/replace-regexp) What I don't understand: you replace one string constant with another - so why the hustle with regular expressions? To replace 2 blanks with one do a normal replace of these exact strings. If you want to replace " [Single] " with " " - do a normal replace. ---
**Author:** ![DHoude](https://community.mp3tag.de/letter_avatar_proxy/v4/letter/d/74df32/32.png) [@DHoude](https://community.mp3tag.de/u/DHoude)\ **Post date:** [February 13, 2015, 6:07pm UTC](https://community.mp3tag.de/t/replace-with-reg-exp-not-working-on-field-with/16596/3 "2015-02-13T18:07:12Z")
> [@ohrenkino](#): > > What I don't understand: you replace one string constant with another - so why the hustle with regular expressions? Mostly my misunderstanding of what I am doing, Lol. Seriously, I know enough to be dangerous. Glad that was such an easy fix. Thanks for your time, makes more sense why my first try did not work. ---
**Author:** ![DHoude](https://community.mp3tag.de/letter_avatar_proxy/v4/letter/d/74df32/32.png) [@DHoude](https://community.mp3tag.de/u/DHoude)\ **Post date:** [February 13, 2015, 6:58pm UTC](https://community.mp3tag.de/t/replace-with-reg-exp-not-working-on-field-with/16596/4 "2015-02-13T18:58:20Z")
Is there a wild card for the Replace function? I am working on another instance where I don't care what data is in a field (empty or not), I would just like to replace that field with "XYZ" data. I just can't save an Action unless I have something in the "Original" field of the Replace action. ---
**Author:** ![ohrenkino](https://community.mp3tag.de/user_avatar/community.mp3tag.de/ohrenkino/32/4843_2.png) [@ohrenkino](https://community.mp3tag.de/u/ohrenkino)\ **Post date:** [February 13, 2015, 7:04pm UTC](https://community.mp3tag.de/t/replace-with-reg-exp-not-working-on-field-with/16596/5 "2015-02-13T19:04:34Z")
if you want to replace something, then at least a little bit has to be there. So "replace" only works with existing data. If you want to set a certain value into a field, select all the files where this should happen. Now you may either use the tag panel, enter the data into the field, save the data. Or: create an action of the type "Format value" for the field, set the data in "format string" and apply it. Or: use the extended tags dialogue (Alt-T) and enter the data either as a new field or as a modification as a result of an "edit" ---
**Author:** ![DHoude](https://community.mp3tag.de/letter_avatar_proxy/v4/letter/d/74df32/32.png) [@DHoude](https://community.mp3tag.de/u/DHoude)\ **Post date:** [February 13, 2015, 7:20pm UTC](https://community.mp3tag.de/t/replace-with-reg-exp-not-working-on-field-with/16596/6 "2015-02-13T19:20:12Z")
Yea, I actually am a Music Video DJ. I wanted to replace the "ITUNESMEDIATYPE" with "Music Video" so that iTunes does not see them as a "Home Movie". Then I can use them as if they were songs and I can put them in playlists. For some reason iTunes does not update this tag when you change it. So if it is ever added again, I have to go into movies and change it to Music Video before I can see it as a song. Thanks again! ---
**Author:** ![ohrenkino](https://community.mp3tag.de/user_avatar/community.mp3tag.de/ohrenkino/32/4843_2.png) [@ohrenkino](https://community.mp3tag.de/u/ohrenkino)\ **Post date:** [February 13, 2015, 9:38pm UTC](https://community.mp3tag.de/t/replace-with-reg-exp-not-working-on-field-with/16596/7 "2015-02-13T21:38:37Z")
the compilation field is also not updated in itunes ... the only way for these fields to get updated in itunes to my experience is to delete the entries from itunes and then re-import the files into itunes again. ---
**Author:** ![system](https://community.mp3tag.de/uploads/default/original/2X/c/ce7035d426cb755a7916793326d23b465222a407.png) [@system](https://community.mp3tag.de/u/system)\ **Post date:** [February 9, 2026, 12:25pm UTC](https://community.mp3tag.de/t/replace-with-reg-exp-not-working-on-field-with/16596/8 "2026-02-09T12:25:32Z")
Closed on February 9, 2026, 12:25pm UTC