case-converter-tools/regex-tester.html at master · laolin5564/case-converter-tools · GitHub

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<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Regex Tester Online Free - Test Regular Expressions Live | Case Converter Tools</title>
    <meta name="description" content="Free online regex tester. Test and validate regular expressions with live matching and syntax highlighting. Debug regex patterns with real-time results and match groups.">
    <meta name="keywords" content="regex tester, regex validator, regexp tester online, regular expression tester, test regex online, regex debugger, regex pattern tester, regex match, regex101 alternative">
    <link rel="canonical" href="https://case-converter.laolin.ai/regex-tester.html">
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    <link rel="stylesheet" href="style.css">
    <meta property="og:title" content="Regex Tester Online Free - Test Regular Expressions Live | Case Converter Tools">
    <meta property="og:description" content="Free online regex tester. Test and validate regular expressions with live matching and syntax highlighting. Debug regex patterns with real-time results and match groups.">
    <meta property="og:url" content="https://case-converter.laolin.ai/regex-tester.html">
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    <meta property="og:site_name" content="Case Converter Tools">
    <meta name="twitter:card" content="summary">
    <meta name="twitter:title" content="Regex Tester Online Free - Test Regular Expressions Live | Case Converter Tools">
    <meta name="twitter:description" content="Free online regex tester. Test and validate regular expressions with live matching and syntax highlighting. Debug regex patterns with real-time results and match groups.">
    <script type="application/ld+json">
{
  "@context": "https://schema.org",
  "@type": "FAQPage",
  "mainEntity": [
    {
      "@type": "Question",
      "name": "How do I test a regular expression online?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Enter your regex pattern in the pattern field and your test string in the text area. The tool highlights all matches in real-time, showing match groups, positions, and capture groups. It supports JavaScript regex syntax with all flags (g, i, m, s)."
      }
    },
    {
      "@type": "Question",
      "name": "What regex flags are supported?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "The tester supports all JavaScript regex flags: g (global - find all matches), i (case-insensitive), m (multiline - ^ and $ match line boundaries), s (dotAll - dot matches newlines), and u (unicode - full Unicode support)."
      }
    },
    {
      "@type": "Question",
      "name": "Can I see capture groups in my regex matches?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Yes! The tool displays all capture groups for each match, showing both named and numbered groups with their matched values and positions. This is invaluable for debugging complex patterns with multiple capture groups."
      }
    }
  ]
}
</script>
</head>
<body>
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    <main>
        <section class="hero">
            <h1>Regex Tester Online Free</h1>
            <p>Test and validate regular expressions with live matching</p>
        </section>

        <section class="tool-section" id="toolSection">
            <!-- Tool UI will be inserted by JS -->
        </section>

        <section class="seo-content">
            <h2>What is Regex Tester?</h2>
            <p>A regex tester lets you write and test regular expressions against sample text in real-time. As you type your pattern, matches are instantly highlighted, making it easy to debug and refine your regex patterns.</p>
            <p>Our Regex Tester supports full JavaScript regular expression syntax including flags (global, case-insensitive, multiline, dotAll). It shows match groups, captures, and provides clear feedback on pattern errors.</p>
            <p>Whether you're writing data validation rules, parsing log files, or building text extraction patterns, this tool dramatically speeds up regex development and testing.</p>

            <h2>How to Use Regex Tester</h2>
            <ol>
                <li>Enter your regular expression pattern</li>
                <li>Add flags (g for global, i for case-insensitive, m for multiline)</li>
                <li>Paste test text in the input area</li>
                <li>Matches are highlighted in real-time as you type</li>
            </ol>

            <h2>Why Use Our Regex Tester?</h2>
            <ul>
                <li><strong>100% Free:</strong> No registration, no limits, completely free to use</li>
                <li><strong>Privacy First:</strong> All processing happens in your browser - no server uploads</li>
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            </ul>
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        <section class="faq">
            <h2>Frequently Asked Questions</h2>
            <details>
                <summary>How do I test a regular expression online?</summary>
                <p>Enter your regex pattern in the pattern field and your test string in the text area. The tool highlights all matches in real-time, showing match groups, positions, and capture groups. It supports JavaScript regex syntax with all flags (g, i, m, s).</p>
            </details>
            <details>
                <summary>What regex flags are supported?</summary>
                <p>The tester supports all JavaScript regex flags: g (global - find all matches), i (case-insensitive), m (multiline - ^ and $ match line boundaries), s (dotAll - dot matches newlines), and u (unicode - full Unicode support).</p>
            </details>
            <details>
                <summary>Can I see capture groups in my regex matches?</summary>
                <p>Yes! The tool displays all capture groups for each match, showing both named and numbered groups with their matched values and positions. This is invaluable for debugging complex patterns with multiple capture groups.</p>
            </details>
        </section>

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                    <h3>Unix Timestamp Converter</h3>
                    <p>Convert Unix timestamps to readable dates and vice versa</p>
                </a>
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