Regex Tester & Debugger
Test regular expressions in real time with match highlighting, group captures, and common presets. Everything runs in your browser.
How It Works
Write your regex
Type or paste a regular expression pattern. Use flag checkboxes to toggle global, case-insensitive, multiline, or dot-all modes.
Enter test text
Paste or type the text you want to test against. Matches are highlighted instantly as you type.
Inspect matches
See match count, individual matches, and capture groups. Copy matches or use a preset to get started quickly.
Why Use a Regex Tester?
Regular expressions are powerful but tricky to get right. A live regex tester lets you iterate on patterns instantly, see exactly what matches, and debug capture groups without running your code.
This tool highlights matches in real time, shows capture groups for each match, and provides common presets for email, URL, phone, IP, and date patterns. No data is sent to any server — everything runs in your browser.
How the regex tester works
Enter a URL or text. Get instant analysis with actionable insights.
Enter your URL or content
Provide the input for the regex tester. Our tool analyzes it using proven SEO and technical standards.
Instant analysis
The regex tester processes your input and delivers a detailed breakdown of issues and recommendations.
Fix issues and improve
Follow the specific recommendations to improve your scores. Re-run the check after making changes to verify improvements.
Frequently asked questions
Common questions about the regex tester.
What is Regex Tester?
Regex Tester is a free tool that helps you test regular expressions with real-time match highlighting. supports all flags (g, i, m, s), group captures, common presets (email, url, phone, ip).
Is this tool really free?
Yes, Regex Tester is 100% free to use. No signup required for most features. You can use it as many times as you need.
How does this tool work?
Simply enter your information in the form, click the action button, and get your results instantly. The tool processes your request and returns useful data or generated content.
Can I use this for commercial purposes?
Yes, you can use the output from Regex Tester for commercial projects, personal websites, and business purposes without restrictions.
Do I need to create an account?
No account or signup needed. Regex Tester works instantly in your browser. For advanced features and unlimited usage, consider upgrading to RobotSpeed.
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