Regex Tools

Regex Tool

Regex Tool runs a JavaScript regular expression against your text in the browser, with live match highlighting, a count, and capture groups.

Client-sideRuns entirely in your browser — your data never leaves your device.

Regex Tool is a free Regex Tools utility that runs entirely in your browser — nothing you enter is uploaded.

Test text
Matches




Cheat sheet — common tokens
\d
digit 0-9
\w
word char (A-Za-z0-9_)
\s
whitespace
\b
word boundary
.
any character
[abc]
one of a, b, c
[^abc]
not a, b, or c
a|b
a or b
a*
zero or more a
a+
one or more a
a?
optional a
a{2,4}
2 to 4 of a
^ $
start / end
(...)
capture group
(?:...)
non-capture group



  
How to use Regex Tool

  
    
      
  1. Type or paste your pattern and test string into Regex Tool's input area.
    2. 
      
  2. Tune the Pattern, Flags controls before you process.
    3. 
      
  3. Watch the output update instantly while you adjust the pattern and test string.
    4. 
      
  4. When it looks right, Copy matches to save it.
    5. 
  

  
About this tool

  
Everything Regex Tool does happens on your own device. Regex Tool runs your pattern locally with the JavaScript engine and shows captures live.

  
Flags and group captures are surfaced so you can refine the pattern quickly. Nothing you enter is uploaded, and it keeps working offline once the page has loaded.

  
Frequently asked questions

  

      
What is Regex Tool for?
Regex Tool runs entirely on your device: add your input using the Pattern, Flags controls, and it processes it locally in real time.

      
Is Regex Tool free to use?
Yes — Regex Tool is completely free, with no usage limits.

      
Does Regex Tool upload my data?
No — Regex Tool processes everything locally in your browser, so nothing you enter is uploaded or stored.

      
Which regex flavor does Regex Tool use?
Regex Tool runs your pattern with the browser's own JavaScript regex engine, live and on your device.

      
Does Regex Tool work on mobile?
Yes — Regex Tool is just a web page and runs on any modern browser, including phones and tablets.

  

  
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