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 = /M(\d{1,3})[-_]\d{1,4}(CCU?|)/gm; // Alternative syntax using RegExp constructor // const regex = new RegExp('M(\\d{1,3})[-_]\\d{1,4}(CCU?|)', 'gm') const str = `DOA000281_ICS_U-M1-300_R-Zero_S.TAB DOA000281_ICS_U-M10-300_R-Zero_S.TAB DOA000281_ICS_U-M100-300_R-Zero_S.TAB DOA000281_ICS_U-M2-300_R-Zero_S.TAB DOA000281_ICS_U-M200-300CCU_R-Zero_S.TAB DOA000281_ICS_U-M200-300_R-Zero_S.TAB DOA000281_ICS_U-M30-300CCU_R-Zero_S.TAB DOA000281_ICS_U-M30-300_R-Zero_S.TAB DOA000281_ICS_U-M5-300_R-Zero_S.TAB DOA000281_ICS_U-M50-300_R-Zero_S.TAB DOA_000533_ICS_100y180s_0y0sMax.tab DOA_000533_ICS_10y180s_0y0sMax.tab DOA_000533_ICS_1y180s_0y0sMax.tab DOA_000533_ICS_200ccy180s_0y0sMax.tab DOA_000533_ICS_200y180s_0y0sMax.tab DOA_000533_ICS_2y180s_0y0sMax.tab DOA_000533_ICS_30ccy180s_0y0sMax.tab DOA_000533_ICS_30y180s_0y0sMax.tab DOA_000533_ICS_50y180s_0y0sMax.tab DOA_000533_ICS_5y180s_0y0sMax.tab CFA_AUG2018_2D DOA_000537_ICS_100y600s_0y0sMax.TAB CFA_AUG2018_2D DOA_000537_ICS_10y600s_0y0sMax.TAB CFA_AUG2018_2D DOA_000537_ICS_1y600s_0y0sMax.TAB CFA_AUG2018_2D DOA_000537_ICS_200ccy600s_0y0sMax.TAB CFA_AUG2018_2D DOA_000537_ICS_200y600s_0y0sMax.TAB CFA_AUG2018_2D DOA_000537_ICS_2y600s_0y0sMax.TAB CFA_AUG2018_2D DOA_000537_ICS_30ccy600s_0y0sMax.TAB CFA_AUG2018_2D DOA_000537_ICS_30y600s_0y0sMax.TAB CFA_AUG2018_2D DOA_000537_ICS_50y600s_0y0sMax.TAB CFA_AUG2018_2D DOA_000537_ICS_5y600s_0y0sMax.TAB DOA000557_ICS_U-M1-60_R-Zero_S_2D.TAB DOA000557_ICS_U-M10-60_R-Zero_S_2D.TAB DOA000557_ICS_U-M100-60_R-Zero_S_2D.TAB DOA000557_ICS_U-M2-60_R-Zero_S_2D.TAB DOA000557_ICS_U-M200-60CCU_R-Zero_S_2D.TAB DOA000557_ICS_U-M200-60_R-Zero_S_2D.TAB DOA000557_ICS_U-M30-60CCU_R-Zero_S_2D.TAB DOA000557_ICS_U-M30-60_R-Zero_S_2D.TAB DOA000557_ICS_U-M5-60_R-Zero_S_2D.TAB DOA000557_ICS_U-M50-60_R-Zero_S_2D.TAB DOA000616_617 ICS U-M1-60_R-ZERO_Summer.TAB DOA000616_617 ICS U-M10-60_R-ZERO_Summer.TAB DOA000616_617 ICS U-M100-60_R-ZERO_Summer.TAB DOA000616_617 ICS U-M2-60_R-ZERO_Summer.TAB DOA000616_617 ICS U-M200-60CCU_R-ZERO_Summer.TAB DOA000616_617 ICS U-M200-60_R-ZERO_Summer.TAB DOA000616_617 ICS U-M30-60CCU_R-ZERO_Summer.TAB DOA000616_617 ICS U-M30-60_R-ZERO_Summer.TAB DOA000616_617 ICS U-M5-60_R-ZERO_Summer.TAB DOA000616_617 ICS U-M50-60_R-ZERO_Summer.TAB DOA000674_ICS_U_M100_120_R_Zero_S.TAB DOA000674_ICS_U_M10_120_R_Zero_S.TAB DOA000674_ICS_U_M1_120_R_Zero_S.TAB DOA000674_ICS_U_M200_120CCU_R_Zero_S.TAB DOA000674_ICS_U_M200_120_R_Zero_S.TAB DOA000674_ICS_U_M2_120_R_Zero_S.TAB DOA000674_ICS_U_M30_120CCU_R_Zero_S.TAB DOA000674_ICS_U_M30_120_R_Zero_S.TAB DOA000674_ICS_U_M50_120_R_Zero_S.TAB DOA000674_ICS_U_M5_120_R_Zero_S.TAB DOA002372_ICS_U_M100_120_R_Zero_S_2D.TAB DOA002372_ICS_U_M10_120_R_Zero_S_2D.TAB DOA002372_ICS_U_M1_120_R_Zero_S_2D.TAB DOA002372_ICS_U_M200_120CC_R_Zero_S_2D.TAB DOA002372_ICS_U_M200_120_R_Zero_S_2D.TAB DOA002372_ICS_U_M2_120_R_Zero_S_2D.TAB DOA002372_ICS_U_M30_120CC_R_Zero_S_2D.TAB DOA002372_ICS_U_M30_120_R_Zero_S_2D.TAB DOA002372_ICS_U_M50_120_R_Zero_S_2D.TAB DOA002372_ICS_U_M5_120_R_Zero_S_2D.TAB `; // 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