# How to detect units mismatch **URL:** \ **Category:** Technical Support\ **Created:** [October 29, 2021, 3:10pm UTC](https://forum.xbench.net/t/how-to-detect-units-mismatch/837 "2021-10-29T15:10:21Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![nari](https://avatars.discourse-cdn.com/v4/letter/n/f17d59/32.png) [@nari](https://forum.xbench.net/u/nari)\ **Post date:** [October 29, 2021, 3:10pm UTC](https://forum.xbench.net/t/how-to-detect-units-mismatch/837/1 "2021-10-29T15:10:21Z")
Hi all, Could you please teach me how to detect the following error using the regular expression in the checklist? ![ex](https://canada1.discourse-cdn.com/flex035/uploads/xbench/original/1X/0977e74eba90e64d5bfc03d1ab281bb3679be256.png) The following regular expression only works if there is a mistake in the first unit. * * * ```auto Source: "([0-9])=1 mm" Target: -"@1 mm" Powersearch: On Seach Mode: Regular Expression ``` * * * Thank you! ---
**Author:** ![omartin](https://yyz1.discourse-cdn.com/flex035/user_avatar/forum.xbench.net/omartin/32/82_2.png) [@omartin](https://forum.xbench.net/u/omartin)\ **Post date:** [October 29, 2021, 3:34pm UTC](https://forum.xbench.net/t/how-to-detect-units-mismatch/837/2 "2021-10-29T15:34:16Z")
You must create more than one checklist entry, depending on the number of appearances of mm in source. 2 instances: Source: `"([0-9]+)=1 mm.*([0-9]+)=2 mm"` Target: `-"@1 mm" OR -"@2 mm"` PowerSearch and Match Whole Word: On. Search Mode: Regular Expressions. 3 instances: Source: `"([0-9]+)=1 mm.*([0-9]+)=2 mm.*([0-9]+)=3 mm"` Target: `-"@1 mm" OR -"@2 mm" OR -"@3 mm"` PowerSearch, Match Whole Word, Normalize Whitespaces: On. Search Mode: Regular Expressions. ---
**Author:** ![nari](https://avatars.discourse-cdn.com/v4/letter/n/f17d59/32.png) [@nari](https://forum.xbench.net/u/nari)\ **Post date:** [October 29, 2021, 3:53pm UTC](https://forum.xbench.net/t/how-to-detect-units-mismatch/837/3 "2021-10-29T15:53:58Z")
Thank you omartin, It worked! 😂 👌