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RegEx Tester

Regular expression (RegEx) tester to validate RegEx with syntax highlighter.

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RegEx Tester

  • What is a regular expression?

    A regular expression (regex, regexp or rational expression) is a sequence of characters that specifies a search pattern. Usually these patterns are used by string-searching algorithms for find or find and replace operations on strings, or for input validation.

  • Is this RegEx Tester free to use?

    Yes, it's completely free to use.

  • How was this RegEx Tester made?

    This RegEx Tester is powered by a [Retool app] (https://retool.com), and is using an [embedded app] (https://retool.com/products/embed) feature, allowing you to easily turn internal tools and utilities like this into public, customer-facing apps. See our other [RegEx generator tool](https://retool.com/utilities/regex-generator), [CSV API generator](https://retool.com/utilities/generate-api-from-csv), [mock data API generator](https://retool.com/utilities/generate-api-from-mock-data), and [CSV app generator](https://retool.com/utilities/generate-app-from-csv).

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Company
About
Careers
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Terms of usePrivacy policySecurityTrust CenterSite map
© Retool 2025