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

const regex = /\(?(\b(Gen(?:esis)?|Exo(?:dus)?|Lev(?:iticus)?|Num(?:bers)?|Deut(?:eronomy)?|Josh(?:ua)?|Judg(?:es)?|Ru(?:th)?|(?:1st|1|First)\ Sam(?:uel)?|(?:2nd|2|Second)\ Sam(?:uel)?|(?:1st|1|First)\ Kings|(?:2nd|2|Second)\ Kings|(?:1st|1|First)\ Chr(?:onicles|on)?|(?:2nd|2|Second)\ Chr(?:onicles|on)?|Ezr(?:a)?|Neh(?:emiah)?|Est(?:her)?|Job|Psa(?:lms?)?|Prov(?:erbs)?|Eccles(?:iastes)?|Songs|(?:Song\ of\ )?Solomon|Isa(?:iah)?|Jer(?:emiah)?|Lam(?:entations)?|Eze(?:kiel)?|Dan(?:iel)?|Hos(?:ea)?|Joel|Am(?:os)?|Obad(?:iah)?|Jon(?:ah)?|Micah|Na(?:hum)?|Hab(?:akkuk)?|Zeph(?:aniah)?|Hagg(?:ai)?|Zech(?:ariah)?|Mal(?:achi)?|Matt(?:hew)?|Mark|Luke|John|Acts|Rom(?:ans)?|(?:1st|1|First)\ Cor(?:inthians)?|(?:2nd|2|Second)\ Cor(?:inthians)?|Gal(?:atians)?|Eph(?:esians)?|Phil(?:ippians)?|Col(?:ossians)?|(?:1st|1|First)\ Thess(?:alonians)?|(?:2nd|2|Second)\ Thess(?:alonians)?|(?:1st|1|First)\ Tim(?:othy)?|(?:2nd|2|Second)\ Timothy|Tit(?:us)?|Philem(?:on)?|Heb(?:rews)?|James|(?:1st|1|First)\ Peter|(?:2nd|2|Second)\ Peter|(?:1st|1|First)\ John|(?:2nd|2|Second)\ John|(?:3rd|3|Third)\ John|Jud(?:e)?|Rev(?:elation)?)\b\s?(\b(?:[1-9]\d?|1[0-4]\d|150)\b(?!\s*-\s*\d+\b:)(?:\s*-\s*\b(?:[1-9]\d?|1[0-4]\d|150)\b)?(?!\s*:\s*,))(?:\s*:\s*(?!\s*,)((?:(?:\s*,\s*)?\b(?:[1-9]\d?|1[0-6]\d|17[0-6])\b(?:\s*-\s*\b(?:[1-9]\d?|1[0-6]\d|17[0-6])\b)?)+))?)\)?/gmi; // Alternative syntax using RegExp constructor // const regex = new RegExp('\\(?(\\b(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?(\\b(?:[1-9]\\d?|1[0-4]\\d|150)\\b(?!\\s*-\\s*\\d+\\b:)(?:\\s*-\\s*\\b(?:[1-9]\\d?|1[0-4]\\d|150)\\b)?(?!\\s*:\\s*,))(?:\\s*:\\s*(?!\\s*,)((?:(?:\\s*,\\s*)?\\b(?:[1-9]\\d?|1[0-6]\\d|17[0-6])\\b(?:\\s*-\\s*\\b(?:[1-9]\\d?|1[0-6]\\d|17[0-6])\\b)?)+))?)\\)?', 'gmi') const str = `SHOULD MATCH: # Single chapters only: 2nd Kings 1 2 Kings 1 Second Kings 1 Genesis 1 (Genesis 1) Gen 1 (Gen 1) matthew 4 1 chr 1 2nd Chron 3 1st Chronicles 8 # Single chapter with single verse: Gen 1:1 Genesis 1:1 (Gen 1:1) # Single chapter with range of verses: Ezra 1:1-3 Hos 150:175-176 # Single chapter with comma-separated verses: Daniel 5:6,7 Daniel 1:2,3,4 # Range of chapters: Genesis 1-5 Ruth 99-150 SHOULD NOT MATCH: # Verse only Job :3 # Range of chapters WITH verse: Psalms 1-3:4 # Range of chapters WITH range of verses: Proverbs 33-44:55-66 # Chapter with comma before verse: Solomon 5:,4 `; // Reset `lastIndex` if this regex is defined globally // regex.lastIndex = 0; let m; while ((m = regex.exec(str)) !== null) { // This is necessary to avoid infinite loops with zero-width matches if (m.index === regex.lastIndex) { regex.lastIndex++; } // The result can be accessed through the `m`-variable. m.forEach((match, groupIndex) => { console.log(`Found match, group ${groupIndex}: ${match}`); }); }

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 JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions