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

const regex = /VSID_W_MAX_TRAN_DT.+?=(?=\s) (?<VSID_W_MAX_TRAN_DT>[^\s]+)/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('VSID_W_MAX_TRAN_DT.+?=(?=\\s) (?<VSID_W_MAX_TRAN_DT>[^\\s]+)', 'gm') const str = `VMID_COUNT =========== 20,588,655 % Total % Received % Xferd Average Speed Time Time Time Current Dload Upload Total Spent Left Speed Table.+.+?(?=\\.)\\W*(opcode_tedc_cs_gmr_id_delta)\\W.+?(?=,+)\\,\\s+numRows\\=+(?<LogTime>[^\\,]+) Loading data to table gmr.opcode_tedc_cs_gmr_id_delta Table gmr.opcode_tedc_cs_gmr_id_delta stats: [numFiles=5, numRows=8986691, totalSize=937732401, rawDataSize=928745710] 0 0 0 0 0 0 0 0 --:--:-- --:--:-- --:--:-- 0 100 997 100 997 0 0 114k 0 --:--:-- --:--:-- --:--:-- 162k 0 0 0 397 0 0 1650 0 --:--:-- --:--:-- --:--:-- 1650 VSID_W_MAX_TRAN_DT ========== 9,070,691 % Total % Received % Xferd Average Speed Time Time Time Current Dload Upload Total Spent Left Speed 0 0 0 0 0 0 0 0 --:--:-- --:--:-- --:--:-- 0 100 997 100 997 0 0 108k 0 --:--:-- --:--:-- --:--:-- 139k 0 0 0 403 0 0 944 0 --:--:-- --:--:-- --:--:-- 944 NON_PSP_VSID_COUNT =========== 39,869,169 % Total % Received % Xferd Average Speed Time Time Time Current Dload Upload Total Spent Left Speed 0 0 0 0 0 0 0 0 --:--:-- --:--:-- --:--:-- 0 100 997 100 997 0 0 112k 0 --:--:-- --:--:-- --:--:-- 162k 0 0 0 398 0 0 7223 0 --:--:-- --:--:-- --:--:-- 7223 PSP_VSID_COUNT =========== 45,083 sendmail: warning: inet_protocols: disabling IPv6 name/address support: Address family not supported by protocol postdrop: warning: inet_protocols: disabling IPv6 name/address support: Address family not supported by protocol [send_coll_stats.sh:] Sent e-mail with collection stats /jobs/prod/proclib/CMLS_HADOOP_proc_v02.ksh: line 75: print: command not found /jobs/prod/proclib/CMLS_trailer.ksh: line 9: print: command not found`; // 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