Regex Tester
Test a regular expression against text, highlight matches, and inspect capture groups.
マッチ数 / Matches: 0
How to use
- Enter a regular expression in "Pattern" (no need for surrounding
/or quotes) - Combine flags such as
g,i,m,s,uin "Flags" (gis applied internally even if omitted) - Paste the text you want to match against in "Test string"
- Matches are highlighted in yellow, with a list of matches and capture groups shown below
Everything runs in your browser using the native RegExp; there is no server communication.
Example
With pattern \d+, flags g, and test string Order has 12 items, totaling 450 yen, 12 and 450 are highlighted and two matches are listed.
FAQ
What happens if I enter an invalid regular expression?
An error message is shown when the pattern or flags are invalid.
Are backreferences and named capture groups supported?
Yes, any syntax supported by JavaScript's RegExp works here.
Is there a limit on the number of matches?
Up to 1000 matches are shown per run, to avoid infinite loops.
Is my data stored anywhere?
No. Everything runs in your browser and disappears when you reload the page.
Category:Developer
Tags:regexregexppatterntestdeveloper
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