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

/
/
gmi

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 = "\\(?\\b(?P<book_name>Gen(?:esis)?|Exo(?:dus)?|Lev(?:iticus)?|Num(?:bers)?|Deut(?:eronomy)?|Josh(?:ua)?|Judg(?:es)?|Ru(?:th)?|(?:1st|1|First)\\ Sam(?:uel)?|(?:2nd|2|Second)\\ Sam(?:uel)?|(?:1st|1|First)\\ Kings|(?:2nd|2|Second)\\ Kings|(?:1st|1|First)\\ Chr(?:onicles|on)?|(?:2nd|2|Second)\\ Chr(?:onicles|on)?|Ezr(?:a)?|Neh(?:emiah)?|Est(?:her)?|Job|Psa(?:lms?)?|Prov(?:erbs)?|Eccles(?:iastes)?|Songs|(?:Song\\ of\\ )?Solomon|Isa(?:iah)?|Jer(?:emiah)?|Lam(?:entations)?|Eze(?:kiel)?|Dan(?:iel)?|Hos(?:ea)?|Joel|Am(?:os)?|Obad(?:iah)?|Jon(?:ah)?|Micah|Na(?:hum)?|Hab(?:akkuk)?|Zeph(?:aniah)?|Hagg(?:ai)?|Zech(?:ariah)?|Mal(?:achi)?|Matt(?:hew)?|Mark|Luke|John|Acts|Rom(?:ans)?|(?:1st|1|First)\\ Cor(?:inthians)?|(?:2nd|2|Second)\\ Cor(?:inthians)?|Gal(?:atians)?|Eph(?:esians)?|Phil(?:ippians)?|Col(?:ossians)?|(?:1st|1|First)\\ Thess(?:alonians)?|(?:2nd|2|Second)\\ Thess(?:alonians)?|(?:1st|1|First)\\ Tim(?:othy)?|(?:2nd|2|Second)\\ Timothy|Tit(?:us)?|Philem(?:on)?|Heb(?:rews)?|James|(?:1st|1|First)\\ Peter|(?:2nd|2|Second)\\ Peter|(?:1st|1|First)\\ John|(?:2nd|2|Second)\\ John|(?:3rd|3|Third)\\ John|Jud(?:e)?|Rev(?:elation)?)\\b\\s?(?P<chapter>\\b(?:150|1[0-4]\\d|[1-9]\\d|[1-9])\\b(?!\\s*-\\s*\\d+\\b:)(?:\\s*-\\s*\\b(?:150|1[0-4]\\d|[1-9]\\d|[1-9])\\b)?(?!\\s*:\\s*,))(?:\\s*:\\s*(?!\\s*,)(?P<verse>(?:(?:\\s*,\\s*)?\\b(?:17[0-6]|1[0-6]\\d|[1-9]\\d|[1-9])\\b(?:\\s*-\\s*\\b(?:17[0-6]|1[0-6]\\d|[1-9]\\d|[1-9])\\b)?)+))?\\)?"; final String string = "SHOULD MATCH:\n" + "# Single chapters only:\n" + " 2nd Kings 1 2 Kings 1 Second Kings 1\n" + " Genesis 1 (Genesis 1) Gen 1 (Gen 1)\n" + " matthew 4\n" + " 1 chr 1 2nd Chron 3 1st Chronicles 8\n\n" + "# Single chapter with single verse:\n" + " Gen 1:1 Genesis 1:1 (Gen 1:1)\n\n" + "# Single chapter with range of verses:\n" + " Ezra 1:1-3 Hos 150:175-176\n\n" + "# Single chapter with comma-separated verses:\n" + " Daniel 5:6,7 Daniel 1:2,3,4\n\n" + "# Range of chapters:\n" + " Genesis 1-5 Ruth 99-150\n\n\n" + "SHOULD NOT MATCH:\n" + "# Verse only\n" + " Job :3\n\n" + "# Range of chapters WITH verse:\n" + " Psalms 1-3:4\n\n" + "# Range of chapters WITH range of verses:\n" + " Proverbs 33-44:55-66\n\n" + "# Chapter with comma before verse:\n" + " Solomon 5:,4\n"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE | Pattern.CASE_INSENSITIVE); 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