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

/
/
gms

Test String

Code Generator

Language

Generated Code

const regex = /!!mstart!!(.*)!!mend!!/gms; // Alternative syntax using RegExp constructor // const regex = new RegExp('!!mstart!!(.*)!!mend!!', 'gms') const str = `!!mstart!! <tr style='mso-yfti-irow:6'> <td class="hidden" width="100%" colspan=6 valign=top style='width:100.0%;border:solid windowtext 1.0pt; border-top:none;mso-border-top-alt:solid windowtext .5pt;mso-border-alt:solid windowtext .5pt; background:#FBE4D5;mso-background-themecolor:accent2;mso-background-themetint: 51;padding:.1in 0in 0in 0in'> <p class=MsoNormal style='margin-bottom:12.0pt;tab-stops:162.75pt'><span style='font-size:18.0pt;font-family:"Calibri Light",sans-serif;mso-ascii-theme-font: major-latin;mso-hansi-theme-font:major-latin;mso-bidi-theme-font:major-latin; color:black;mso-color-alt:windowtext'><span style='mso-spacerun:yes'> </span>Mailing Projects</span><span style='font-size:18.0pt;font-family:"Calibri Light",sans-serif; mso-ascii-theme-font:major-latin;mso-hansi-theme-font:major-latin;mso-bidi-theme-font: major-latin'><o:p></o:p></span></p> <table class=MsoTableGrid border=1 cellspacing=0 cellpadding=0 width="100%" style='border-collapse:collapse;mso-table-layout-alt:fixed;border:none; mso-border-alt:solid windowtext .5pt;mso-yfti-tbllook:1184;mso-padding-alt: .1in .1in .1in .1in'> <tr style='mso-yfti-irow:0;mso-yfti-firstrow:yes'> <td width=227 colspan=2 valign=top style='width:169.9pt;border-top:solid windowtext 1.0pt; border-left:none;border-bottom:none;border-right:solid windowtext 1.0pt; mso-border-top-alt:solid windowtext .5pt;mso-border-right-alt:solid windowtext .5pt; padding:.1in .1in .1in .1in'> <p class=MsoNormal>Postal Service:<o:p></o:p></p> </td> <td width=123 valign=top style='width:92.6pt;border-top:solid windowtext 1.0pt; border-left:none;border-bottom:none;border-right:solid windowtext 1.0pt; mso-border-left-alt:solid windowtext .5pt;mso-border-top-alt:solid windowtext .5pt; mso-border-left-alt:solid windowtext .5pt;mso-border-right-alt:solid windowtext .5pt; padding:.1in .1in .1in .1in'> <p class=MsoNormal>Postage Paid by:<o:p></o:p></p> </td> <td width=345 colspan=2 valign=top style='width:258.8pt;border-top:solid windowtext 1.0pt; border-left:none;border-bottom:none;border-right:solid windowtext 1.0pt; mso-border-left-alt:solid windowtext .5pt;mso-border-top-alt:solid windowtext .5pt; mso-border-left-alt:solid windowtext .5pt;mso-border-right-alt:solid windowtext .5pt; padding:.1in .1in .1in .1in'> <p class=MsoNormal>Package Components:<o:p></o:p></p> </td> <td width=345 colspan=3 valign=top style='width:258.85pt;border:none; border-top:solid windowtext 1.0pt;mso-border-left-alt:solid windowtext .5pt; mso-border-top-alt:solid windowtext .5pt;mso-border-left-alt:solid windowtext .5pt; padding:.1in .1in .1in .1in'> <p class=MsoNormal>Package Dimensions (inches):<o:p></o:p></p> </td> </tr> <tr style='mso-yfti-irow:1'> <td width=227 colspan=2 valign=top style='width:169.9pt;border-top:none; border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt; mso-border-bottom-alt:solid windowtext .5pt;mso-border-right-alt:solid windowtext .5pt; padding:.1in .1in .1in .1in'> <ul style='margin-top:0in' type=disc> <li class=MsoListParagraph style='margin-left:0in;mso-list:l1 level1 lfo2'>\$PostalService\$<o:p></o:p></li> </ul> </td> <td width=123 valign=top style='width:92.6pt;border-top:none;border-left: none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt; mso-border-left-alt:solid windowtext .5pt;mso-border-left-alt:solid windowtext .5pt; mso-border-bottom-alt:solid windowtext .5pt;mso-border-right-alt:solid windowtext .5pt; padding:.1in .1in .1in .1in'> \$PostagePaidBy\$ </td> <td width=345 colspan=2 valign=top style='width:258.8pt;border-top:none; border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt; mso-border-left-alt:solid windowtext .5pt;mso-border-left-alt:solid windowtext .5pt; mso-border-bottom-alt:solid windowtext .5pt;mso-border-right-alt:solid windowtext .5pt; padding:.1in .1in .1in .1in'> <p class=MsoNormal>\$PackageComponents\$<o:p></o:p></p> </td> <td width=345 colspan=3 valign=top style='width:258.85pt;border:none; border-bottom:solid windowtext 1.0pt;mso-border-left-alt:solid windowtext .5pt; mso-border-left-alt:solid windowtext .5pt;mso-border-bottom-alt:solid windowtext .5pt; padding:.1in .1in .1in .1in'> <p class=MsoNormal>\$PackageDimensions\$<o:p></o:p></p> </td> </tr> <tr style='mso-yfti-irow:2'> <td width=1040 colspan=8 valign=top style='width:780.15pt;border:none; border-bottom:solid windowtext 1.0pt;mso-border-top-alt:solid windowtext .5pt; mso-border-top-alt:solid windowtext .5pt;mso-border-bottom-alt:solid windowtext .5pt; padding:.1in .1in .1in .1in'> <p class=MsoNormal><b><span style='font-size:14.0pt;font-family:"Calibri Light",sans-serif; mso-ascii-theme-font:major-latin;mso-hansi-theme-font:major-latin; mso-bidi-theme-font:major-latin'>Package Detail<o:p></o:p></span></b></p> </td> </tr> <tr style='mso-yfti-irow:3'> <td width=173 valign=top style='width:129.45pt;border:none;border-right: solid windowtext 1.0pt;mso-border-top-alt:solid windowtext .5pt;mso-border-top-alt: solid windowtext .5pt;mso-border-right-alt:solid windowtext .5pt; padding:.1in .1in .1in .1in'> <p class=MsoNormal>Package 1<o:p></o:p></p> </td> <td width=177 colspan=2 valign=top style='width:133.05pt;border:none; border-right:solid windowtext 1.0pt;mso-border-top-alt:solid windowtext .5pt; mso-border-left-alt:solid windowtext .5pt;mso-border-top-alt:solid windowtext .5pt; mso-border-left-alt:solid windowtext .5pt;mso-border-right-alt:solid windowtext .5pt; padding:.1in .1in .1in .1in'> <p class=MsoNormal>Package 2<o:p></o:p></p> </td> <td width=173 valign=top style='width:129.4pt;border:none;border-right: solid windowtext 1.0pt;mso-border-top-alt:solid windowtext .5pt;mso-border-left-alt: solid windowtext .5pt;mso-border-top-alt:solid windowtext .5pt;mso-border-left-alt: solid windowtext .5pt;mso-border-right-alt:solid windowtext .5pt; padding:.1in .1in .1in .1in'> <p class=MsoNormal>Package 3<o:p></o:p></p> </td> <td width=173 valign=top style='width:129.4pt;border:none;border-right: solid windowtext 1.0pt;mso-border-top-alt:solid windowtext .5pt;mso-border-left-alt: solid windowtext .5pt;mso-border-top-alt:solid windowtext .5pt;mso-border-left-alt: solid windowtext .5pt;mso-border-right-alt:solid windowtext .5pt; padding:.1in .1in .1in .1in'> <p class=MsoNormal>Package 4<o:p></o:p></p> </td> <td width=173 colspan=2 valign=top style='width:129.4pt;border:none; border-right:solid windowtext 1.0pt;mso-border-top-alt:solid windowtext .5pt; mso-border-left-alt:solid windowtext .5pt;mso-border-top-alt:solid windowtext .5pt; mso-border-left-alt:solid windowtext .5pt;mso-border-right-alt:solid windowtext .5pt; padding:.1in .1in .1in .1in'> <p class=MsoNormal>Package 5<o:p></o:p></p> </td> <td width=173 valign=top style='width:129.45pt;border:none;mso-border-top-alt: solid windowtext .5pt;mso-border-left-alt:solid windowtext .5pt;padding: .1in .1in .1in .1in'> <p class=MsoNormal>Package 6<o:p></o:p></p> </td> </tr> <tr style='mso-yfti-irow:4'> <td width=173 valign=top style='width:129.45pt;border-top:none;border-left: none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt; mso-border-bottom-alt:solid windowtext .5pt;mso-border-right-alt:solid windowtext .5pt; padding:.1in .1in .1in .1in'> <ul style='margin-top:0in' type=disc> \$Package1\$ </ul> </td> <td width=177 colspan=2 valign=top style='width:133.05pt;border-top:none; border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt; mso-border-left-alt:solid windowtext .5pt;mso-border-left-alt:solid windowtext .5pt; mso-border-bottom-alt:solid windowtext .5pt;mso-border-right-alt:solid windowtext .5pt; padding:.1in .1in .1in .1in'> <ul style='margin-top:0in' type=disc> \$Package2\$ </ul> </td> <td width=173 valign=top style='width:129.4pt;border-top:none;border-left: none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt; mso-border-left-alt:solid windowtext .5pt;mso-border-left-alt:solid windowtext .5pt; mso-border-bottom-alt:solid windowtext .5pt;mso-border-right-alt:solid windowtext .5pt; padding:.1in .1in .1in .1in'> <ul style='margin-top:0in' type=disc> \$Package3\$ </ul> </td> <td width=173 valign=top style='width:129.4pt;border-top:none;border-left: none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt; mso-border-left-alt:solid windowtext .5pt;mso-border-left-alt:solid windowtext .5pt; mso-border-bottom-alt:solid windowtext .5pt;mso-border-right-alt:solid windowtext .5pt; padding:.1in .1in .1in .1in'> <ul style='margin-top:0in' type=disc> \$Package4\$ </ul> </td> <td width=173 colspan=2 valign=top style='width:129.4pt;border-top:none; border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt; mso-border-left-alt:solid windowtext .5pt;mso-border-left-alt:solid windowtext .5pt; mso-border-bottom-alt:solid windowtext .5pt;mso-border-right-alt:solid windowtext .5pt; padding:.1in .1in .1in .1in'> <ul style='margin-top:0in' type=disc> \$Package5\$ </ul> </td> <td width=173 valign=top style='width:129.45pt;border:none;border-bottom: solid windowtext 1.0pt;mso-border-left-alt:solid windowtext .5pt; mso-border-left-alt:solid windowtext .5pt;mso-border-bottom-alt:solid windowtext .5pt; padding:.1in .1in .1in .1in'> <ul style='margin-top:0in' type=disc> \$Package6\$ </ul> </td> </tr> <tr style='mso-yfti-irow:5'> <td width=173 valign=top style='width:129.45pt;border:none;border-right: solid windowtext 1.0pt;mso-border-top-alt:solid windowtext .5pt;mso-border-top-alt: solid windowtext .5pt;mso-border-right-alt:solid windowtext .5pt; padding:.1in .1in .1in .1in'> <p class=MsoNormal>Package Weight <span style='font-size:8.0pt'>(estimated)</span>:<o:p></o:p></p> </td> <td width=177 colspan=2 valign=top style='width:133.05pt;border:none; border-right:solid windowtext 1.0pt;mso-border-top-alt:solid windowtext .5pt; mso-border-left-alt:solid windowtext .5pt;mso-border-top-alt:solid windowtext .5pt; mso-border-left-alt:solid windowtext .5pt;mso-border-right-alt:solid windowtext .5pt; padding:.1in .1in .1in .1in'> <p class=MsoNormal>Data Work Required:<o:p></o:p></p> </td> <td width=173 valign=top style='width:129.4pt;border:none;border-right: solid windowtext 1.0pt;mso-border-top-alt:solid windowtext .5pt;mso-border-left-alt: solid windowtext .5pt;mso-border-top-alt:solid windowtext .5pt;mso-border-left-alt: solid windowtext .5pt;mso-border-right-alt:solid windowtext .5pt; padding:.1in .1in .1in .1in'> <p class=MsoNormal>Operations Required:<o:p></o:p></p> </td> <td width=259 colspan=2 valign=top style='width:194.1pt;border:none; border-right:solid windowtext 1.0pt;mso-border-top-alt:solid windowtext .5pt; mso-border-left-alt:solid windowtext .5pt;mso-border-top-alt:solid windowtext .5pt; mso-border-left-alt:solid windowtext .5pt;mso-border-right-alt:solid windowtext .5pt; padding:.1in .1in .1in .1in'> <p class=MsoNormal>Mailing Instructions:<o:p></o:p></p> </td> <td width=259 colspan=2 valign=top style='width:194.15pt;border:none; mso-border-top-alt:solid windowtext .5pt;mso-border-left-alt:solid windowtext .5pt; padding:.1in .1in .1in .1in'> <p class=MsoNormal>Additional Comments:<o:p></o:p></p> </td> </tr> <tr style='mso-yfti-irow:6;mso-yfti-lastrow:yes'> <td width=173 valign=top style='width:129.45pt;border:none;border-right: solid windowtext 1.0pt;mso-border-right-alt:solid windowtext .5pt; padding:.1in .1in .1in .1in'> <p class=MsoNormal>\$WeightOfPackage\$<o:p></o:p></p> </td> <td width=177 colspan=2 valign=top style='width:133.05pt;border:none; border-right:solid windowtext 1.0pt;mso-border-left-alt:solid windowtext .5pt; mso-border-left-alt:solid windowtext .5pt;mso-border-right-alt:solid windowtext .5pt; padding:.1in .1in .1in .1in'> \$RequiredDataWork\$ </td> <td width=173 valign=top style='width:129.4pt;border:none;border-right: solid windowtext 1.0pt;mso-border-left-alt:solid windowtext .5pt; mso-border-left-alt:solid windowtext .5pt;mso-border-right-alt:solid windowtext .5pt; padding:.1in .1in .1in .1in'> <p class=MsoNormal>\$OperationsRequired\$<o:p></o:p></p> </td> <td width=259 colspan=2 valign=top style='width:194.1pt;border:none; border-right:solid windowtext 1.0pt;mso-border-left-alt:solid windowtext .5pt; mso-border-left-alt:solid windowtext .5pt;mso-border-right-alt:solid windowtext .5pt; padding:.1in .1in .1in .1in'> <p class=MsoNormal>\$SpecialMailingInstructions\$<o:p></o:p></p> </td> <td width=259 colspan=2 valign=top style='width:194.15pt;border:none; mso-border-left-alt:solid windowtext .5pt;padding:.1in .1in .1in .1in'> <p class=MsoNormal>\$MailAdditionalComments\$<o:p></o:p></p> </td> </tr> <![if !supportMisalignedColumns]> <tr height=0> <td width=162 style='border:none'></td> <td width=32 style='border:none'></td> <td width=123 style='border:none'></td> <td width=159 style='border:none'></td> <td width=146 style='border:none'></td> <td width=86 style='border:none'></td> <td width=60 style='border:none'></td> <td width=151 style='border:none'></td> </tr> <![endif]> </table> <p class=MsoNormal><o:p></o:p></p> </td> </tr> !!mend!!`; // 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