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Regex Tester

A powerful regular expression tester with real-time matching, syntax highlighting, and detailed match information. Test your regex patterns instantly and see all matches, capturing groups, and indices.

Includes a pattern library with common regex patterns, find & replace functionality, and code generation for JavaScript, Python, and PHP.

1

Regular Expression

Ready
/ /
2

Test String

3

Results

Enter a pattern to begin
Matches will be highlighted here...
#MatchIndexLength
No matches yet
Match #GroupValueIndex
No groups captured

Use $& for full match, $1, $2 for groups, $` for text before, $' for text after

Replace result will appear here...


Pattern Library
Common

Email Address
[a-zA-Z0-9...]

URL
https?://...

Phone Number
^[\+]?[(]?...

IP Address (IPv4)
\b\d{1,3}\....
Dates & Times

Date (YYYY-MM-DD)
\d{4}-\d{2}...

Date (DD/MM/YYYY)
\d{2}\/\d{2}...

Time (24h)
([01]?[0-9]...
Web & Code

HTML Tag
<([a-z]+)...

Hex Colour
#([A-Fa-f0...]

Code Comments
\/\*[\s\S]...
Validation

Strong Password
^(?=.*[a-z]...

Username
^[a-zA-Z0-9...

UK Postcode
^[A-Z]{1,2}...

US ZIP Code
^\d{5}(-\d...
Text Processing

Words
\b\w+\b

Sentence Endings
[.!?]+

Leading/Trailing Space
^\s+|\s+$

Multiple Spaces
\s{2,}


Quick Reference
.Any character
\dDigit [0-9]
\wWord char [a-zA-Z0-9_]
\sWhitespace
^Start of string/line
$End of string/line
*0 or more
+1 or more
?0 or 1
{n}Exactly n times
{n,m}Between n and m
[abc]Character class
[^abc]Not in class
(abc)Capture group
(?:abc)Non-capture group
a|bAlternation (or)
\bWord boundary
(?=...)Positive lookahead
(?!...)Negative lookahead


History

No history yet
How to Use the Regex Tester
  • 
Enter your pattern: Type your regular expression in the pattern field. The tool validates your regex in real-time and shows any errors.
  • 
Set your flags: Click the flag buttons (g, i, m, s, u) to toggle options like global matching, case insensitivity, and multiline mode.
  • 
Add test text: Enter or paste the text you want to test against in the test string area. Matches are highlighted instantly.
  • 
Explore results: Use the tabs to view highlighted matches, a table of all matches, captured groups, or perform find & replace operations.
  • 
Generate code: Switch to the Code tab to get ready-to-use code snippets for JavaScript, Python, PHP, or C#.
Regex Flags Explained
  • 
g (Global): Find all matches rather than stopping after the first match.
  • 
i (Case Insensitive): Match both uppercase and lowercase characters interchangeably.
  • 
m (Multiline): Make ^ and $ match the start/end of each line, not just the whole string.
  • 
s (Dotall): Make the dot (.) match newline characters as well.
  • 
u (Unicode): Enable full Unicode support for patterns and strings.
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