Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

/
/
gm

Test String

Code Generator

Language

Generated Code

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "maxiobe request response game"; final String string = "index.php:\n\n" + "<?php\n" + "// index.php – Aufgabe 3 (Bootstrap, Bereichsauswahl, Validierung, Versuchszähler)\n" + "declare(strict_types=1);\n" + "session_start();\n\n" + "/* ------------------ Helper ------------------ */\n" + "function h(string $s): string { return htmlspecialchars($s, ENT_QUOTES, 'UTF-8'); }\n" + "function resetGame(): void {\n" + " unset($_SESSION['randomNumber'], $_SESSION['tries'], $_SESSION['min'], $_SESSION['max'], $_SESSION['guesses']);\n" + "}\n\n" + "/* ------------------ Init ------------------ */\n" + "$alerts = []; // sammelt Bootstrap-Alerts [ ['type'=>'warning|danger|success|info','text'=>'...'] ]\n" + "if (!isset($_SESSION['tries'])) { $_SESSION['tries'] = 0; }\n" + "if (!isset($_SESSION['guesses'])) { $_SESSION['guesses'] = []; }\n\n" + "/* ------------------ Actions ------------------ */\n" + "if ($_SERVER['REQUEST_METHOD'] === 'POST') {\n\n" + " // Exit / Neues Spiel\n" + " if (isset($_POST['exit'])) {\n" + " resetGame();\n" + " header('Location: ' . $_SERVER['SCRIPT_NAME']);\n" + " exit();\n" + " }\n\n" + " // Start-Spiel mit Bereich (min/max)\n" + " if (isset($_POST['startgame'])) {\n" + " $min = $_POST['min'] ?? '1';\n" + " $max = $_POST['max'] ?? '10';\n\n" + " // Grundvalidierung: ganzzahlig\n" + " $validInts = ctype_digit(strval($min)) && ctype_digit(strval($max));\n" + " if (!$validInts) {\n" + " $alerts[] = ['type'=>'danger','text'=>'Bitte nur ganze Zahlen für <b>Min</b> und <b>Max</b> verwenden.'];\n" + " } else {\n" + " $min = (int)$min;\n" + " $max = (int)$max;\n\n" + " // Logische Prüfungen\n" + " if ($min < 0) { $alerts[] = ['type'=>'warning','text'=>'Der Minimalwert darf nicht negativ sein.']; }\n" + " if ($max <= $min) { $alerts[] = ['type'=>'warning','text'=>'<b>Max</b> muss größer als <b>Min</b> sein.']; }\n" + " if ($max - $min > 10000) { $alerts[] = ['type'=>'warning','text'=>'Der Bereich ist zu groß. Wähle einen kleineren Abstand (max. 10.000).']; }\n\n" + " if (!$alerts) {\n" + " $_SESSION['min'] = $min;\n" + " $_SESSION['max'] = $max;\n" + " $_SESSION['randomNumber'] = rand($min, $max);\n" + " $_SESSION['tries'] = 0;\n" + " $_SESSION['guesses'] = [];\n" + " $alerts[] = ['type'=>'primary','text'=>\"Spiel gestartet! Rate die Zahl zwischen <b>{$min}</b> und <b>{$max}</b>.\"];\n" + " }\n" + " }\n" + " }\n\n" + " // Rateversuch\n" + " if (isset($_POST['try']) && isset($_SESSION['randomNumber'])) {\n" + " $raw = $_POST['enteredNumber'] ?? '';\n\n" + " // Prüfung: Zahl eingegeben?\n" + " if ($raw === '' || !preg_match('/^-?\\d+$/', trim((string)$raw))) {\n" + " $alerts[] = ['type'=>'warning','text'=>'Bitte eine <b>ganze Zahl</b> eingeben.'];\n" + " } else {\n" + " $guess = (int)$raw;\n" + " $min = $_SESSION['min'] ?? 1;\n" + " $max = $_SESSION['max'] ?? 10;\n\n" + " // Bereichsprüfung\n" + " if ($guess < $min || $guess > $max) {\n" + " $alerts[] = ['type'=>'warning','text'=>\"Dein Tipp liegt <b>außerhalb</b> des Bereichs <b>{$min}–{$max}</b>.\"];\n" + " } else {\n" + " $secret = (int)$_SESSION['randomNumber'];\n" + " $_SESSION['tries']++;\n" + " $_SESSION['guesses'][] = $guess;\n\n" + " if ($guess === $secret) {\n" + " $t = (int)$_SESSION['tries'];\n" + " $alerts[] = ['type'=>'success','text'=>\"Zahl erraten 🎉 – du brauchtest <b>{$t}</b> Versuch\" . ($t === 1 ? '' : 'e') . \".\"];\n" + " // Nach Erfolg: Neues Spiel möglich (Reset-Button rendern), Zahl bleibt aber bis Exit,\n" + " // damit man die Success-Meldung sieht und \"Neues Spiel\" klicken kann.\n" + " // Alternativ direkt resetGame(); echo Link – aber wir bleiben konsistent mit Aufgabe 2.\n" + " } else {\n" + " $hint = ($guess > $secret) ? 'zu hoch' : 'zu niedrig';\n" + " $alerts[] = ['type'=>'danger','text'=>\"Leider falsch – dein Tipp ist <b>{$hint}</b>.\"];\n" + " }\n" + " }\n" + " }\n" + " }\n" + "}\n\n" + "/* ------------------ View (HTML) ------------------ */\n" + "?>\n" + "<!doctype html>\n" + "<html lang=\"de\">\n" + "<head>\n" + " <meta charset=\"utf-8\"/>\n" + " <meta name=\"viewport\" content=\"width=device-width, initial-scale=1\"/>\n" + " <title>Ratespiel – Aufgabe 3</title>\n" + " <link rel=\"stylesheet\" href=\"assets/bootstrap/css/bootstrap.min.css\">\n" + "</head>\n" + "<body>\n" + "<div class=\"container py-4\">\n" + " <h1 class=\"mb-4\">Ratespiel – Aufgabe 3</h1>\n\n" + " <?php foreach ($alerts as $a): ?>\n" + " <div class=\"alert alert-<?php echo h($a['type']); ?>\" role=\"alert\">\n" + " <?php echo $a['text']; ?>\n" + " </div>\n" + " <?php endforeach; ?>\n\n" + " <?php if (isset($_SESSION['randomNumber'])): ?>\n" + " <!-- Laufendes Spiel -->\n" + " <div class=\"card mb-3\">\n" + " <div class=\"card-body\">\n" + " <h5 class=\"card-title\">Dein Tipp</h5>\n" + " <form class=\"row g-3\" action=\"<?php echo h($_SERVER['SCRIPT_NAME']); ?>\" method=\"post\" name=\"form\">\n" + " <div class=\"col-sm-6 col-md-4\">\n" + " <input class=\"form-control\" type=\"number\" name=\"enteredNumber\"\n" + " placeholder=\"Zahl <?php echo (int)($_SESSION['min'] ?? 1); ?>–<?php echo (int)($_SESSION['max'] ?? 10); ?>\"\n" + " min=\"<?php echo (int)($_SESSION['min'] ?? 1); ?>\"\n" + " max=\"<?php echo (int)($_SESSION['max'] ?? 10); ?>\">\n" + " </div>\n" + " <div class=\"col-auto\">\n" + " <button class=\"btn btn-success\" type=\"submit\" name=\"try\" value=\"1\">Raten</button>\n" + " </div>\n" + " <div class=\"col-auto\">\n" + " <button class=\"btn btn-outline-secondary\" type=\"submit\" name=\"exit\" value=\"1\">Neues Spiel</button>\n" + " </div>\n" + " </form>\n" + " <p class=\"mt-3 mb-0\">\n" + " Bereich: <span class=\"badge bg-secondary\">\n" + " <?php echo (int)($_SESSION['min'] ?? 1); ?>–<?php echo (int)($_SESSION['max'] ?? 10); ?>\n" + " </span>\n" + " &nbsp;|&nbsp;\n" + " Versuche: <span class=\"badge bg-info text-dark\"><?php echo (int)$_SESSION['tries']; ?></span>\n" + " </p>\n" + " <?php if (!empty($_SESSION['guesses'])): ?>\n" + " <p class=\"mt-2 mb-0\">\n" + " Bisherige Tipps:\n" + " <?php foreach ($_SESSION['guesses'] as $g): ?>\n" + " <span class=\"badge bg-light text-dark\"><?php echo (int)$g; ?></span>\n" + " <?php endforeach; ?>\n" + " </p>\n" + " <?php endif; ?>\n" + " </div>\n" + " </div>\n\n" + " <?php if (!empty($alerts) && end($alerts)['type'] === 'success'): ?>\n" + " <!-- Bei Erfolg optional Hinweis-Card -->\n" + " <div class=\"alert alert-success\" role=\"alert\">\n" + " Glückwunsch! Du kannst oben auf <b>Neues Spiel</b> klicken, um erneut zu starten.\n" + " </div>\n" + " <?php endif; ?>\n\n" + " <?php else: ?>\n" + " <!-- Startseite mit Bereichsauswahl -->\n" + " <div class=\"card\">\n" + " <div class=\"card-body\">\n" + " <h5 class=\"card-title\">Spiel starten</h5>\n" + " <form class=\"row g-3\" action=\"<?php echo h($_SERVER['SCRIPT_NAME']); ?>\" method=\"post\" name=\"form\">\n" + " <div class=\"col-sm-4 col-md-3\">\n" + " <label class=\"form-label\" for=\"min\">Min</label>\n" + " <input class=\"form-control\" type=\"number\" id=\"min\" name=\"min\" value=\"1\" min=\"0\" step=\"1\" required>\n" + " </div>\n" + " <div class=\"col-sm-4 col-md-3\">\n" + " <label class=\"form-label\" for=\"max\">Max</label>\n" + " <input class=\"form-control\" type=\"number\" id=\"max\" name=\"max\" value=\"10\" min=\"1\" step=\"1\" required>\n" + " </div>\n" + " <div class=\"col-12\">\n" + " <button class=\"btn btn-primary\" type=\"submit\" name=\"startgame\" value=\"1\">Spielstart</button>\n" + " </div>\n" + " </form>\n" + " <p class=\"text-muted mt-2 mb-0\">Tipp: Wähle z. B. 1–100 für mehr Herausforderung.</p>\n" + " </div>\n" + " </div>\n" + " <?php endif; ?>\n\n" + "</div>\n" + "<script src=\"assets/bootstrap/js/bootstrap.bundle.min.js\"></script>\n" + "</body>\n" + "</html>\n\n" + "form try:\n\n" + "<?php\n" + "// form_try.part.php\n" + "?>\n" + "<form action=\"<?php echo htmlspecialchars($_SERVER['SCRIPT_NAME']); ?>\" method=\"post\" name=\"form\">\n" + " <input type=\"text\" name=\"enteredNumber\" placeholder=\"Zahl zwischen 1 und 10\" />\n" + " <input type=\"submit\" value=\"Raten\" name=\"try\" />\n" + " <input type=\"submit\" value=\"Exit\" name=\"exit\" />\n" + "</form>\n\n\n" + "form start:\n\n" + "<?php\n" + "// form_start.part.php\n" + "?>\n" + "<form action=\"<?php echo htmlspecialchars($_SERVER['SCRIPT_NAME']); ?>\" method=\"post\" name=\"form\">\n" + " <input type=\"submit\" value=\"Spielstart\" name=\"startgame\" />\n" + "</form>\n\n\n"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE); final Matcher matcher = pattern.matcher(string); while (matcher.find()) { System.out.println("Full match: " + matcher.group(0)); for (int i = 1; i <= matcher.groupCount(); i++) { System.out.println("Group " + i + ": " + matcher.group(i)); } } } }

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Java, please visit: https://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html