Tamim Labs

RegEx Tester

Write a pattern, see every match highlighted as you type, inspect capture groups, preview a replacement and read a plain-English breakdown. Everything runs in your browser — your pattern and text never leave your device.

Runs in your browser — nothing is uploaded

Regular expression

//

Common patterns

Flags legend
g
global — find every match, not just the first
i
ignore case
m
multiline — ^ and $ also match at line breaks
s
dotall — . also matches line breaks
u
unicode mode
y
sticky — match only from the current position

Test text

0 characters

Matches

Waiting for a pattern

Enter a pattern to see highlighted matches.

Replace

→
The replaced text appears here.

What this pattern does

Enter a pattern to read a plain-English, token-by-token breakdown.

Code

const regex = //;
const text = "your text here";

const matches = text.match(regex); // null when there is no match
console.log(matches);

What RegEx Tester does

  • Live match highlighting as you type
  • Match navigation with a live match counter
  • Per-group colour coding and copy-as-JSON/CSV export
  • Flags: global, ignore case, multiline, dotall, unicode, sticky
  • Capture groups and named groups listed
  • Plain-English explanation of the pattern
  • A common-patterns library (email, URL, UUID and more)
  • Code snippets for JavaScript, Python, Go and PHP

How to use it

  1. 01

    Open the RegEx Tester.

  2. 02

    Enter a pattern and toggle flags.

  3. 03

    Paste test text to see matches highlighted with their groups.

  4. 04

    Copy an explanation or a ready-made code snippet.

Common questions

Is my pattern or test text uploaded?
No. Patterns and text run on the browser's own RegExp engine, entirely on your device.
What does the tool explain?
It gives a plain-English reading of the pattern and lists every capture group, plus ready-to-paste code snippets for JavaScript, Python, Go and PHP.
Can it help me write a pattern from scratch?
Yes. A common-patterns library (email, URL, UUID and more) gives you a working starting point you can then edit and test live.

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