# Regex to detect domain name mismatches
**URL:** https://forum.xbench.net/t/regex-to-detect-domain-name-mismatches/826
**Category:** Technical Support
**Created:** [October 10, 2021, 1:56pm UTC](https://forum.xbench.net/t/regex-to-detect-domain-name-mismatches/826 "2021-10-10T13:56:32Z")
**Posts on this page:** 7
**Page:** 1
### Author:  [@LuisHermogenes](https://forum.xbench.net/u/LuisHermogenes)
#### Post date: [October 10, 2021, 1:56pm UTC](https://forum.xbench.net/t/regex-to-detect-domain-name-mismatches/826/1 "2021-10-10T13:56:32Z")
Hi all,
I am trying to create a regular expression that would detect an exact mismatch of a domain name between source and target.
For instance, I have “[sitename.com](http://sitename.com)”, “[sitename.de](http://sitename.de)”, “sitename.com.ca”, and “sitename.com.mx”.
I can easily enough find any mismatches to mismatches where “[sitename.com](http://sitename.com)” is not used.
For example, this detects if “[sitename.de](http://sitename.de)” is used in the source and not in the target:
Source: “((sitename.[a-z]{1,3})=1”
Target: -@1
However, because the last two (“sitename.com.ca” and “sitename.com.mx”) have “.com” in the name, Xbench considers them a match (even if I select “Match whole word” or I use the “End of word” regex (e.g., “sitename.[a-z]{1,3}\>”).)
I’ve tried even creating a Key term list with the domain names, but it seems Xbench considers the second period (“sitename.com.XX”) the end of the word, so it is thinks “[sitename.com](http://sitename.com)” is the full match.
Any help here? Thanks!
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### Author:  [@omartin](https://forum.xbench.net/u/omartin)
#### Post date: [October 10, 2021, 9:49pm UTC](https://forum.xbench.net/t/regex-to-detect-domain-name-mismatches/826/2 "2021-10-10T21:49:15Z")
Hi Luis,
I would use the following regex to find all those domain names:
Source: `"(sitename((\.[a-z]+))+)=1"`
Target: `-@1`
Search mode: regular expressions
Match Whole Word and PowerSearch: on.
By the way, replace sitename with the domain you want to find.
An alternative to get all site names, would be to change the source term to `"([a-z0-9\-]{1,63}((\.[a-z]+))+)=1"`
However, you may get too many false errors.
I hope this helps.
Best regards,
Oscar.
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### Author:  [@LuisHermogenes](https://forum.xbench.net/u/LuisHermogenes)
#### Post date: [October 11, 2021, 8:17am UTC](https://forum.xbench.net/t/regex-to-detect-domain-name-mismatches/826/3 "2021-10-11T08:17:02Z")
Hi Óscar,
Thanks for your quick reply! However, the issue is still happening.
It does not detect an issue when the source is “[sitename.com](http://sitename.com)” and target is “sitename.com.ca”, for instance. I think it is because Xbench does not read “sitename.com.ca” as a single full word, but instead reads it as 3 words (sitename, com, and ca); as it considers the period a parsing character.
What can we do?
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### Author:  [@omartin](https://forum.xbench.net/u/omartin)
#### Post date: [October 11, 2021, 8:44am UTC](https://forum.xbench.net/t/regex-to-detect-domain-name-mismatches/826/4 "2021-10-11T08:44:12Z")
The following search works fine:
Source: `"(sitename(\.[a-z]+)+)=1"`
target: `-@1`
Search mode: regular expressions
Match Whole Word and PowerSearch: on.
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### Author:  [@LuisHermogenes](https://forum.xbench.net/u/LuisHermogenes)
#### Post date: [October 11, 2021, 9:51am UTC](https://forum.xbench.net/t/regex-to-detect-domain-name-mismatches/826/5 "2021-10-11T09:51:59Z")
Hi Oscar,
Sure, but I mean the other way around. It will detect when “sitename.com.ca” is in source and not in target appears, but not the other way around.
I tried reverting the expression, and it works:
Source: -@1
target: “(sitename(.[a-z]+)+)=1”
Can you help me confirm this would detect the same issues as in the one you showed me above? I.e.:
Source: “(sitename(.[a-z]+)+)=1”
target: -@1
EDIT: Meaning, would it detect all issues of mismatches in source and target?
Thanks!
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### Author:  [@omartin](https://forum.xbench.net/u/omartin)
#### Post date: [October 11, 2021, 10:19am UTC](https://forum.xbench.net/t/regex-to-detect-domain-name-mismatches/826/6 "2021-10-11T10:19:06Z")
> [@LuisHermogenes](#):
>
> Source: “(sitename(.[a-z]+)+)=1”
> target: -@1
This search will detect all segments that contain a domain name in source but is missing in the target.
You should create a checklist entry for each search.
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### Author:  [@LuisHermogenes](https://forum.xbench.net/u/LuisHermogenes)
#### Post date: [October 11, 2021, 10:42am UTC](https://forum.xbench.net/t/regex-to-detect-domain-name-mismatches/826/7 "2021-10-11T10:42:14Z")
Hi Oscar.
Got it, I’ll create two searches, one for missing in source and one for missing in target.
Thanks!