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Regex Tester
Live regex testing with match highlighting, groups, and replace preview
//g
Flags:
No matches
Test String
Highlighted Matches
Matches highlighted here…
Replace preview…
Easy Tutorial
How to Use Regex Tester in 3 Steps
Follow this quick walkthrough to get optimal results in seconds.
1
Enter Pattern & Flags
Input your regular expression (e.g. [a-z0-9]+) and toggle flags (g, i, m).
2
Provide Test String
Enter the text you want to evaluate.
3
Inspect Matches
View highlighted matches and captured groups in real time.
Engineered for Quality
Key Features & Benefits
Live Matching
Instant visual highlights as you type.
Cloudflare R2 Temporary Storage
Files are processed securely and deleted automatically upon download. No permanent logs or storage.
100% Free & Limitless
No subscription fees, no account registrations, and no artificial throttles.
Technical Specifications & Compatibility
EngineECMAScript (JavaScript Regex)
Got Questions?
Frequently Asked Questions
It uses the ECMAScript (JavaScript) regular expression engine native to your browser.
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