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

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"!!mstart!!(.*)!!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!!") matches = re.finditer(regex, test_str, re.MULTILINE | re.DOTALL) for matchNum, match in enumerate(matches, start=1): print ("Match {matchNum} was found at {start}-{end}: {match}".format(matchNum = matchNum, start = match.start(), end = match.end(), match = match.group())) for groupNum in range(0, len(match.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = match.start(groupNum), end = match.end(groupNum), group = match.group(groupNum))) # Note: for Python 2.7 compatibility, use ur"" to prefix the regex and u"" to prefix the test string and substitution.

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