Regex Tester

Developer Tools

Live regex with match highlights

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//g
Flags:
Add a file · .txt .md .csv .json … · up to 2.00 MB
Full guide, 4 min readRegex from zero: ten patterns and the trap that freezes pagesRead the story behind this tool →
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Regex Tester — at a glance

Write a regular expression and see live which parts of your text match it.

Pattern + text
Pattern: \d+
Text: Order 123 and 45
Match
Matches
Match 1: 123
Match 2: 45

How to use it — step by step

Great for learning regex and for checking patterns before putting them in code.

1

Write the pattern

Type your regular expression without the surrounding slashes.

2

Pick flags

g = all matches, i = ignore case, m = multi-line, s = dot matches new line.

3

Add test text

Paste the text you want to search.

4

See matches

Matches are highlighted with their position and capture groups.

Pro tips

Small things that make the result better.

✦\d means a digit, \w a letter/number, \s a space.
✦Add the g flag to find every match, not just the first.
✦Use ( ) to capture parts of a match (groups).

Quick facts

4 flagsg, i, m and s
Livehighlighting as you type
Groupscapture groups shown
Errorsinvalid patterns flagged

Frequently Asked Questions

What does the g flag do?+

It finds all matches in the text instead of stopping at the first.

What does i do?+

It makes the match ignore upper/lower case differences.

Which regex flavour is used?+

The JavaScript regular expression engine of your browser.

Is my data safe?+

Yes. Everything runs inside your own browser. Your text, files and images are never uploaded to any server.

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