Online Regular Expression Calculator Help

The Online Regular Expression Calculator allows you to build up a regular expression and test it as you go along. You can use the test text supplied, or use your own - either typed in or pasted in.

You can build the regular expression text by typing it in and using the buttons. In addition, you can supply the "modifiers" to determine:

  • Case sensitivity: if you want letters in the regular expression to match regardless of capitals (or not).
  • Global matching: find all matches or replacements in source text. The alternative is for the expression only to match or replace the first one.
  • Multi-line matches: whether matches in the source text can appear over multiple lines. When the matches can be multi-line, the full stop (.) can match new line characters.

Press "Match Line" and only lines that match the expression are placed in the result box.

Press "Replace" to take the whole source with any matches replaced into the result box.

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