Regular Expressions 101

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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
Processing...

Test String

Code Generator

Language

Generated Code

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

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 Python, please visit: https://docs.python.org/3/library/re.html