Live regex matching with capture groups, replace mode, and pattern explanation
Free online regex tester with live matching, capture groups, replace mode, and pattern explanation. Supports JavaScript regex flags g, i, m, s. This tool is built for practical, real-world usage where speed, clarity, and reliable output matter. You can start with the default values, review the result, and then refine inputs step by step to match your exact scenario.
For best results, keep your inputs clean and complete. Double-check units, date ranges, and value formats before you calculate. If you are comparing multiple scenarios, change one variable at a time so you can clearly understand what moved the output.
This page helps when you need a quick answer without switching apps, creating accounts, or installing software. It is suitable for professionals, founders, students, and teams who want transparent logic and immediate outputs.
The tool is designed for guidance and operational calculations. For compliance-critical submissions or legal/financial filings, always verify with your official source rules and current regulations. We regularly improve these pages so they remain practical and dependable for day-to-day work.
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g (global): find all matches. i: case-insensitive. m: ^ and $ match line start/end. s: dot matches newline. u: full Unicode support.
Wrap part of your pattern in parentheses like (\w+). Each group is numbered $1, $2, etc. Use them in replace patterns to rearrange matched text.
Email: [\w.-]+@[\w.-]+\.\w+. URL: https?://[\w.-]+(/\S*)?. Phone: \+?\d{1,3}[-.\s]?\d{3,14}. IP: \d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}
Purpose: Live regex matching, capture groups, replace mode, and pattern explanation.
Free online regex tester with live matching, capture groups, replace mode, and pattern explanation. Supports JavaScript regex flags g, i, m, s.
This page includes tool-specific method notes, edge-case guidance, and reference context to provide substantial user value beyond a basic calculator interface.