Regex Tester
PopularTest regular expressions live with match highlighting, capture groups, and replace mode.
Test text
44 charsPreview
The quick brown fox jumps over 13 lazy dogs.
[The] [quick] [brown] [fox] [jumps] [over] [13] [lazy] [dogs].
Matches
9 foundMatch 1
0 to 3
The
Match 2
4 to 9
quick
Match 3
10 to 15
brown
Match 4
16 to 19
fox
Match 5
20 to 25
jumps
Match 6
26 to 30
over
Match 7
31 to 33
13
Match 8
34 to 38
lazy
Match 9
39 to 43
dogs
Presets
How to use
- 1
Enter your regex pattern
Type your regular expression into the pattern input. Toggle flags like global, case-insensitive, and multiline as needed.
- 2
Add test text
Paste or type the text you want to test against in the textarea. Matches are highlighted in real time.
- 3
Review match details
Check the match info panel for the total number of matches and capture group values for each match.
- 4
Try replace mode
Toggle replace mode to enter a replacement string and preview the substituted output.
Frequently asked questions
What regex flavour does this use?
Can I test capture groups?
Does it support the replace function?
Is my test data sent anywhere?
Test and debug regular expressions in real time. Enter a pattern and test
string to see matches highlighted inline with colour-coded spans. View
match details including capture groups for each match. Toggle regex flags
(global, case-insensitive, multiline, dotAll, unicode) and switch to
replace mode to preview substitutions. Includes presets for common patterns
like email, URL, IP address, and more. All processing runs client-side.