What regex flavour does this use?

JavaScript ECMAScript regex (the browser's native RegExp). Most common patterns (character classes, quantifiers, groups, lookahead) work identically to Python, Java, and .NET regex.

How do I match all occurrences?

Enable the 'g' (global) flag. Without it, only the first match is returned.

How do I do a case-insensitive search?

Enable the 'i' flag to make the match case insensitive.

What does the 'm' flag do?

Multiline mode makes ^ match the start of each line and $ match the end of each line, rather than just the start/end of the whole string.

What does the 's' flag (dotall) do?

Normally, . does not match newline characters. The 's' flag makes . match any character including \n and \r.

How do I match a literal dot or special character?

Escape it with a backslash: \. for a literal dot, \* for a literal asterisk, \( for a literal parenthesis, etc.

Regex Tester — Test Regular Expressions Online with Live Highlighting | Toolivon

Regex Tester — Live Match Highlighting

Test regular expressions with instant highlighting, flag toggles, and a detailed match list.

Regular Expression

//gi

Test String

Matches 11

Hello World! The quick brown fox jumps over the lazy dog.

Match Details

1Hello@0

2World@6

3The@13

4quick@17

5brown@23

6fox@29

7jumps@33

8over@39

9the@44

10lazy@48

11dog@53

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How to Use the Regex Tester

1
Enter your regex pattern
Type your regular expression in the pattern field. The / delimiters are shown for clarity but should not be included in your input.
2
Toggle flags
Enable g (global), i (case insensitive), m (multiline), or s (dotall) flags using the flag buttons.
3
Type your test string
Enter or paste the text you want to test against in the Test String area.
4
See live highlights
All matches are highlighted in amber in the preview area as you type.
5
Review match details
The match list shows each match, its position index, and a copy button for individual matches.

Frequently Asked Questions

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