How To
How to Test Regular Expressions Online
Test and debug regular expressions against sample text instantly in your browser.
Regular expressions (regex) are powerful but hard to write correctly. FileCraft's Regex Tester highlights matches in real time as you type.
Step-by-Step Guide
1
Open FileCraft Regex Tester
Go to filecraft.tools/regex-tester.
2
Enter your pattern
Type your regex pattern in the Pattern field. Flags (i, g, m) can be toggled.
3
Paste test text
Enter or paste the text you want to test against.
4
View matches
Matches are highlighted in real time. Match groups are listed below.
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Open Json Formatter →Pro Tips
- 💡Use the "g" flag for global matching (find all matches, not just the first)
- 💡Use the "i" flag for case-insensitive matching
- 💡Hover over a match to see which capture group it belongs to
Frequently Asked Questions
What regex flavour does FileCraft use?
JavaScript's built-in RegExp engine — the same flavour used in Node.js, Chrome, and most web browsers.