# Case Conversion with regex
**URL:** https://community.mp3tag.de/t/case-conversion-with-regex/2745
**Category:** Support
**Created:** [January 8, 2006, 3:23pm UTC](https://community.mp3tag.de/t/case-conversion-with-regex/2745 "2006-01-08T15:23:35Z")
**Posts on this page:** 7
**Page:** 1
### Author:  [@k00lice](https://community.mp3tag.de/u/k00lice)
#### Post date: [January 8, 2006, 3:23pm UTC](https://community.mp3tag.de/t/case-conversion-with-regex/2745/1 "2006-01-08T15:23:35Z")
First of all, this program is great. Thanks for working so hard.
Anyway, this is what I have a problem with.
I am trying to convert cases of tags to mixed tags.
Example)
I AM SO gooD And a Dog of John -\> I Am So Good And A Dog Of John
:This is how you get when you use mixed conversion.
I do not want some of words to convert to Mixed cases, such as A, An, Of.
So my target is something like this...
Target)
I Am So Good and a Dog of John
I put this regular expression after mixed case conversion
```
Regex (.*) (a |the |of |to |an |and ) and replace with $1 \l$2
```
But this doesn't work as I wanted it to be
Result)
I Am So Good And A Dog of John
The expression above just convert last a, an, of or whatever, but ignores any words before that.
Would you please let me know how I can manage this?
---
### Author:  [@dano](https://community.mp3tag.de/u/dano)
#### Post date: [January 8, 2006, 3:38pm UTC](https://community.mp3tag.de/t/case-conversion-with-regex/2745/2 "2006-01-08T15:38:52Z")
Try this approach:
> [@](#):
>
> RegExp:
> \s(a|the|of|to|an|and)(?=\s)
> Replace:
> $lower($0)
---
### Author:  [@k00lice](https://community.mp3tag.de/u/k00lice)
#### Post date: [January 9, 2006, 1:17am UTC](https://community.mp3tag.de/t/case-conversion-with-regex/2745/3 "2006-01-09T01:17:02Z")
Thanks, Dano! It works and very simple. GREAT!!
---
### Author:  [@immr](https://community.mp3tag.de/u/immr)
#### Post date: [February 8, 2007, 7:58am UTC](https://community.mp3tag.de/t/case-conversion-with-regex/2745/4 "2007-02-08T07:58:37Z")
I tried to add to this so that it won't change to lower case when the word follows a colon, parenthesis, dash or bracket.
(e.g. (This Could Be) The Last Time; Alpha Omega (The Beginning); Interstellar Overdrive: The Alternate Masters)
So I added to RegExp: [^:()[]-]\s(a|the|of|to|an|and)(?=\s)
and left Replace as: $lower($0)
This seemed to work fine until it came across "Yes, The River Knows"
The comma seems to cause a problem: instead of "Yes, the River Knows" I get "Yes River Knows"
I haven't been able to get it to work right, can anyone help out? Thanks.
---
### Author:  [@immr](https://community.mp3tag.de/u/immr)
#### Post date: [February 14, 2007, 4:21am UTC](https://community.mp3tag.de/t/case-conversion-with-regex/2745/5 "2007-02-14T04:21:25Z")
I figured it out.
---
### Author:  [@dano](https://community.mp3tag.de/u/dano)
#### Post date: [February 14, 2007, 2:59pm UTC](https://community.mp3tag.de/t/case-conversion-with-regex/2745/6 "2007-02-14T14:59:45Z")
Good for you, but you might want to tell the others!
Not really a useful post without the information.
---
### Author:  [@system](https://community.mp3tag.de/u/system)
#### Post date: [February 9, 2026, 12:19pm UTC](https://community.mp3tag.de/t/case-conversion-with-regex/2745/7 "2026-02-09T12:19:35Z")