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 = "(.*\\d{5,}.*)|(^(\\,|\\.|\\\\|\\'|\\-|\\?|\\*|\\(|\\@|\\^|\\=|\\/|\\%|\\\").*)|(.*(\\<|\\>|\\[|\\]|\\;).*)|(.*(\\.html|\\.php).*)|^(\\d\\.\\d)|(^\\\\.*)|(^\\%.*\\%)|(\\d{1,3}(((x|\\.|\\.[[:space:]]){1,2})|[[:space:]])\\d{1,3})|.*x$|^0[a-z]*|.{50,}"; final String string = "<script>alert('hai');</script>\n" + "0.8 \n" + "003902\n" + ",eja kerja\n" + ".akeup\n" + "081320266690\n" + "1 set meja kursi\n" + "0elan\n" + "meja makan\n" + "100 meja\n" + "12 cm\n" + "10023995\n" + "]\n" + "\"abcd\"\n" + "\\yj magnolia\n" + "%m087%\n" + "'t. shower set kris prem rev wht ptss-0211-5w \n" + "-tangga/kamar-mandi/1kvigy-jual-title-deck-karpet-anti-licin-bath-mat-anti-slip\n" + "? sarapan✅ lunch crew✅ snack crew✅ video on process undangan ? roundown ✅ backdrops✅ photo booth✅ documentation ✅ rooms hotel ? catering ? panggung ? opening speech ? flag dance ✅ door prizes? seragam ? cue card ?. d . ,\n" + "?meja?\n" + "'merlott mylo set meja makan\n" + "*\"tangga\"*\n" + "@meja\n" + "(u/6)\n" + "*晶杯子\n" + "/*meja*/\n" + "/%meja\n" + "====\n" + "^meja^\n" + "14 pcs radiator cup tester ( top quality ) alat tes kebocoran radiator \n" + "120x200x35 cm jty202 ubah lokasi produk hanya bisa di ambil di lippo plaza kupang (informa) verified brand linotela dikirim oleh ruparupa detail produk\n" + "640 × 640gambar mungkin memiliki hak cipta. pelajari lebih lanjut kuncibengkel\n" + "%meja\n" + "%mp18.html\n" + "100x\n" + "25x25\n" + "250x250\n" + "123. 456\n" + "123.456\n" + "123 456"; 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