RegEx (Regular Expression) online tools

In theoretical computer science and formal language theory, a regular expression (abbreviated regex or regexp) is a sequence of characters that forms a search pattern, mainly for use in pattern matching with strings, or string matching, i.e. “find and replace”-like operations. The concept arose in the 1950s, when the American mathematician Stephen Kleene formalized the description of a regular language, and came into common use with the Unix text processing utilities ed, an editor, and grep (global regular expression print), a filter.

There are many tools to build and test regular expressions. The purpose here is not to draw up a complete list of such tools, but to share the best of the ones I know, ordered by preference (ie completely subjective!)

  1. Rubular
  2. Rubular is a Ruby-based regular expression editor. It’s a handy way to test regular expressions as you write them.
    Definitely my favorite!

  3. Regex101
  4. Online regex tester, debugger with highlighting for PHP, PCRE, Python and JavaScript that highlights pattern and matches on the fly. Features regex quiz and IRC chat box.

  5. reFiddle
  6. A tool for generating and testing regular expressions.

  7. RegexPal
  8. A JavaScript regular expression tester.

  9. Regex Hero
  10. Regex Hero runs directly off of the Regex class library inside Silverlight. I will say that Silverlight is missing the RegexOptions.

  12. Online Regular Expression Tester that supports PHP, Ruby, Python, Javasript. Real-time result and permalink to share regex.

  13. RegViz
  14. RegViz is a tool for debugging JavaScript regular expressions in a visual way. Advanced highlighting helps you to understand the structure and purpose of a regular expression and to detect bugs therein.

If you know of any online tools at least as powerful as those here and who are missing, please share them in a comment; and now it’s time to use some old posts: and
If some

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