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

`
`
img

Test String

Code Generator

Language

Generated Code

const regex = new RegExp('"pack_id": "(.*)"', 'img') const str = `I/okhttp.OkHttpClient: { "route_state": "give_packs", "shelves": [ { "pack_id": "100142009300S2T1599432189", "shelf": "13", "total_goods": 2, "pack_state": "new" }, { "pack_id": "100143022336S5T1599502063", "shelf": "21", "total_goods": 5, "pack_state": "new" }, { "pack_id": "100143367911S2T1599558724", "shelf": "6", "total_goods": 2, "pack_state": "new" }, { "pack_id": "100143699532S5T1599568344", "shelf": "30", "total_goods": 5, "pack_state": "new" }, { "pack_id": "50127475503S1T1599567324", "shelf": "10", "total_goods": 1, "pack_state": "new" }, { "pack_id": "100143773834S4T1599570622", "shelf": "36", "total_goods": 4, "pack_state": "new" }, { "pack_id": "100143789121S1T1599571959", "shelf": "4", "total_goods": 1, "pack_state": "new" }, { "pack_id": "100143772313S1T1599587841", "shelf": "29", "total_goods": 1, "pack_state": "new" }, { "pack_id": "50127216356S2T1599555765", "shelf": "16", "total_goods": 2, "pack_state": "new" }, { "pack_id": "100143911917S9T1599578036", "shelf": "28", "total_goods": 9, "pack_state": "new" }, { "pack_id": "100144040317S3T1599592353", "shelf": "45", "total_goods": 3, "pack_state": "new" }, { "pack_id": "50122511688S10T1599216787", "shelf": "14", "total_goods": 10, "pack_state": "new" }, { "pack_id": "100143883877S3T1599580528", "shelf": "18", "total_goods": 3, "pack_state": "new" }, { "pack_id": "50125998587S5T1599460888", "shelf": "35", "total_goods": 5, "pack_state": "new" }, { "pack_id": "100143065694S7T1599505793", "shelf": "19", "total_goods": 7, "pack_state": "new" }, { "pack_id": "50126023780S18T1599462088", "shelf": "23", "total_goods": 18, "pack_state": "new" }, { "pack_id": "100143257387S1T1599516006", "shelf": "3", "total_goods": 1, "pack_state": "new" }, { "pack_id": "100143204003S8T1599513922", "shelf": "42", "total_goods": 8, "pack_state": "new" }, { "pack_id": "100143474921S10T1599546590", "shelf": "33", "total_goods": 10, "pack_state": "new" }, { "pack_id": "50126884830S5T1599522235", "shelf": "22", "total_goods": 5, "pack_state": "new" }, { "pack_id": "100142045579S1T1599431118", "shelf": "12", "total_goods": 1, "pack_state": "new" } ] }`; // 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