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Online Regex Tester: Test Regular Expressions with Live Matching
Regular expressions are powerful and finicky: one misplaced character and your pattern matches nothing — or worse, everything. An online regex tester shows you matches live as you type, so you can build and debug patterns in seconds instead of guessing.
What a regex tester does
- Live matching — see every match highlighted as you type
- Validation — instant feedback when your pattern is invalid
- Flags — global (g), case-insensitive (i), multiline (m)
- Match details — positions and counts for every hit
Test regex online with Tooly
The Tooly Regex Tester covers it:
- Paste your pattern and test text — matches update live
- Toggle g, i, and m flags with checkboxes
- See match count and each match's position
- 100% client-side — your patterns never leave your browser
Test a regex free — no signup
Open Regex Tester
Open Regex Tester
Handy patterns to start with
\b[\w.-]+@[\w-]+\.[\w.]+\b— emails\+?[0-9\s-]{10,15}— phone numbershttps?:\/\/[\w.-]+— URLs\d{4}-\d{2}-\d{2}— dates (YYYY-MM-DD)
Common pitfalls
- Forgetting to escape
.(use\.for a literal dot) - Missing the
gflag — you only get the first match - Anchors
^/$not matching where you expect in multiline text - Greedy quantifiers matching too much — try
*?for lazy
Frequently Asked Questions
Is this regex tester really free? Yes — unlimited testing, no account, no watermark.
Is my pattern uploaded? No — everything runs in your browser, so your regex and test data stay on your device.
Does it support JavaScript regex syntax? Yes — standard JS regex with g/i/m flags, matching what your code will run.
What else pairs with it? The JSON Formatter and URL Parser are favorite companions for API work.