Regex Tester

Test regular expressions in real time with match highlighting and capture groups

100% In-BrowserNo Server UploadFree, No Signup
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How to Use

  1. Enter a regex pattern

    Type your regex pattern in the input area. No need to wrap it in slashes.

  2. Enter test string

    Type the text you want to match against in the toolbar test string field.

  3. Review results

    Match results appear in real time in the output area, including capture groups.

Regex Tester Examples

Date pattern matching

Input
(\d{4})-(\d{2})-(\d{2})
Output
Match 1: "2024-01-15" (index 0-10)
  Group 1: "2024"
  Group 2: "01"
  Group 3: "15"

Test string: "2024-01-15 meeting"

Email extraction

Input
[\w.+-]+@[\w-]+\.[\w.]+
Output
Match 1: "user@example.com" (index 10-26)

Use the g flag to find all matches

Features

  • Real-time matching as you type
  • Detailed capture group display
  • Flag toggles (g: global, i: case-insensitive, m: multiline, s: dotAll)
  • Match position (index) display
  • Match count summary
  • Local processing (your input is not sent to servers)
  • Dark mode support

FAQ

Do I need to wrap the pattern in slashes?

No. Just enter the pattern itself. Flags can be set using the toolbar toggles.

Are named capture groups supported?

Yes. Named groups using (?<name>...) syntax are displayed with their names.

Is my data sent to a server?

No. Everything runs locally in your browser and nothing is uploaded.