LAnguage: English
OS: Windows (all)
License: Freeware
Virus tested: OK, tested with Avast!, AVG and OfficeScan
Website: http://www.codeproject.com/KB/string/regextester.aspx

Author's description:

With RegEx Tester, you can fully develop and test your regular expression against a target text.
Its UI is designed to aid you in the RegEx development; especially the big and complex ones.
It uses and supports almost ALL of the features available in the .NET RegEx class.

My review:

At only 76Kb size, RegEx Tester allows you to test one or more Regular Expressions before actually using it in some other software. For instance, if in Notepad++, PSPad, Replace Text, you want to search and replace text, and you can't understand why your Regular Expression isn't working, you can discover with RegEx Tester.

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