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 = "(?!((\">)([A-Za-z]|[ء-ي])))=(?=([A-Za-z]|[ء-ي]|\\(|\\)))"; final String string = "<!-- This is an automatically generated file.\n" + " It will be read and overwritten.\n" + " DO NOT EDIT! -->\n" + "<META HTTP-EQUIV=\"Content-Type\" CONTENT=\"text/html; charset=UTF-8\">\n" + "<TITLE>Bookmarks</TITLE>\n" + "<H1>Bookmarks</H1>\n" + "<DL><p>\n\n\n" + "<DT><A HREF=\"https://translate.google.com/details?sl=en&tl=ar&text=groundwork&op=translate\" ADD_DATE=\"1666511420\" ICON=\"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABAAAAAQCAYAAAAf8/9hAAAAAXNSR0IArs4c6QAAAARzQklUCAgICHwIZIgAAAI5SURBVDiNfZJPSFRRFMZ/9743L+efiZrTkE6UhgVNmwaiP0aLaBNEtSgIikDdtGrVKmggaldLIWlZUKs2kVAbUYKIcFEYmRIohKakzpijznv3nhbzJ2eCuXDgci/fOd/3nU9dfbz61GinXwQsgIAAIhA2K6df3EmN0+DoQDn9oEFpVF1tmKaBRmAALZQn1k0XQFx1LZud9Bo1cKVyk/8/lY64rYcjn6empqc9z7Wu64q1YIxFa5FCIXjpVoC74tDf59MehfkcPHobIhCYWY32nin+7o1GIziORkQIhRxEhHjcuehWKA/0+bz54jAxp4k3QWBL77O5CMv5BTyvQDwWQSlV64Et6+1oFibmNGcPWe6e93l4yQfAiOLbUoTiVpF7w88REURKtEWEqoTFvOLoXsu7r5rcBpzssVVjx2csqwsTHOzq5NnIKMtr63Ql2rlwKvPPxCdjIQb7fG6cMCzlFUOjTnUrayTZGW8j3ZPgx8950t0pjhzYh7UWt8yGhRzcfx2q2YiUafqi2FSdjLz/QLjJ43i6F9/3cRwHLVIyi20l28AVGd9zLWwVA1AKYwzWWoIgqA2SALZskt0GFmA238y5YxnS3SlejX3EGFuSEGxuDWnPu1WfJxFQCpTSiIDB5VexlUyqmZZYBBELONQute5ks58i45OL6wCxmMPtmwmSiTBKgdYapRS6cYNMYf8edza8QzN4pY321lA1A5UcNGwAkNxtH1y/3Eyyw0HEIlLSboxhaeXP8F9VPRfd8eYTcAAAAABJRU5ErkJggg==\">underlag/groundwork/foundation/العمل التحضيري/الأساس/</A>\n" + " <DT><H3 ADD_DATE=\"1727566144\" LAST_MODIFIED=\"1727566144\">produksjonsunderlag=production basis=()(أساس الإنتاج )</H3>\n\n" + " </DL><p>\n" + " <DT><H3 ADD_DATE=\"1727566144\" LAST_MODIFIED=\"1727566144\">antitrust==(مكافحة الاحتكار)</H3>\n" + " <DL><p>\n\n" + "(?!(\">([A-Za-z]|[ء-ي])))=(?=([A-Za-z]|[ء-ي]))\n\n" + "x(?=y) x followed by y\n" + "x(?!y) x NOT followed by y\n\n" + "=(?!(\">([A-Za-z]|[ء-ي])))\n\n" + "(?:((\">)(?=([A-Za-z])))\n\n" + "=((?=([A-Za-z]|[ء-ي]))(?!y))\n\n" + "(?!(\">([A-Za-z]|[ء-ي])))(=)(?=([A-Za-z]|[ء-ي]))\n" + "(?!((\">)([A-Za-z]|[ء-ي])))(=)(?:([A-Za-z]|[ء-ي]){1})"; 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