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

/
/
g

Test String

Substitution

Processing...

Code Generator

Generated Code

re = /(\/\*(.|\s)*?\*\/|(\n|\t|\r|\v|\f|\a){1,}|\s(?=\s)|(?<=})\s|(?<={)\s|\s(?={)|\s(?=})|(?<=;)\s|[[:blank:]](?=;)|(?<=:)[[:blank:]]|(?<=,)[[:blank:]])/ str = '@import url(//fonts.googleapis.com/css?family=Open+Sans:300italic,400italic,600italic,300,400,600&subset=latin-ext,latin); /* Generic */ body { font-family: "Open Sans", sans-serif; font-size:13px; background:#fcfcfc; padding:0; margin:8px 8px 0 8px; } textarea {resize:none;outline:none;} a:link, a:hover { color: #2B6FB6; } a:visited { color: #3C2BB6; } .nowrap {white-space: nowrap} /* Forms */ form {margin: 0;} fieldset {margin:0; padding:4px; border:1px solid #dfdfdf; font-family:Verdana, Arial; font-size:10px;} legend {color:#2B6FB6; font-weight:bold;} label.msg {display:none;} label.invalid {color:#EE0000; display:inline;} input.invalid {border:1px solid #EE0000;} input {background:#FFF; border:1px solid #dfdfdf;} input, select, textarea {font-family:Verdana, Arial, Helvetica, sans-serif; font-size:10px;} input, select, textarea {border:1px solid #dfdfdf;} input.radio {border:1px none #000000; background:transparent; vertical-align:middle;} input.checkbox {border:1px none #000000; background:transparent; vertical-align:middle;} .input_noborder {border:0;} /* Buttons */ #insert, #cancel, #apply, .mceActionPanel .button, input.mceButton, .updateButton { display: inline-block; text-decoration: none; border: 1px solid #adadad; margin: 0; padding: 0 10px 1px; font-size: 13px; height: 24px; line-height: 22px; color: #333; cursor: pointer; -webkit-border-radius: 3px; -webkit-appearance: none; border-radius: 3px; white-space: nowrap; -webkit-box-sizing: border-box; -moz-box-sizing: border-box; box-sizing: border-box; background: #fafafa; background-image: -webkit-gradient(linear, left top, left bottom, from(#fafafa), to(#e9e9e9)); background-image: -webkit-linear-gradient(top, #fafafa, #e9e9e9); background-image: -moz-linear-gradient(top, #fafafa, #e9e9e9); background-image: -o-linear-gradient(top, #fafafa, #e9e9e9); background-image: linear-gradient(to bottom, #fafafa, #e9e9e9); text-shadow: 0 1px 0 #fff; -webkit-box-shadow: inset 0 1px 0 #fff; -moz-box-shadow: inset 0 1px 0 #fff; box-shadow: inset 0 1px 0 #fff; } #insert { background: #2ea2cc; background: -webkit-gradient(linear, left top, left bottom, from(#2ea2cc), to(#1e8cbe)); background: -webkit-linear-gradient(top, #2ea2cc 0%,#1e8cbe 100%); background: linear-gradient(top, #2ea2cc 0%,#1e8cbe 100%); filter: progid:DXImageTransform.Microsoft.gradient( startColorstr=\'#2ea2cc\', endColorstr=\'#1e8cbe\',GradientType=0 ); border-color: #0074a2; -webkit-box-shadow: inset 0 1px 0 rgba(120,200,230,0.5); box-shadow: inset 0 1px 0 rgba(120,200,230,0.5); color: #fff; text-decoration: none; text-shadow: 0 1px 0 rgba(0,86,132,0.7); } #cancel:hover, input.mceButton:hover, .updateButton:hover, #cancel:focus, input.mceButton:focus, .updateButton:focus { background: #f3f3f3; background-image: -webkit-gradient(linear, left top, left bottom, from(#fff), to(#f3f3f3)); background-image: -webkit-linear-gradient(top, #fff, #f3f3f3); background-image: -moz-linear-gradient(top, #fff, #f3f3f3); background-image: -ms-linear-gradient(top, #fff, #f3f3f3); background-image: -o-linear-gradient(top, #fff, #f3f3f3); background-image: linear-gradient(to bottom, #fff, #f3f3f3); border-color: #999; color: #222; } #insert:hover, #insert:focus { background: #1e8cbe; background: -webkit-gradient(linear, left top, left bottom, from(#1e8cbe), to(#0074a2)); background: -webkit-linear-gradient(top, #1e8cbe 0%,#0074a2 100%); background: linear-gradient(top, #1e8cbe 0%,#0074a2 100%); filter: progid:DXImageTransform.Microsoft.gradient( startColorstr=\'#1e8cbe\', endColorstr=\'#0074a2\',GradientType=0 ); border-color: #0074a2; -webkit-box-shadow: inset 0 1px 0 rgba(120,200,230,0.6); box-shadow: inset 0 1px 0 rgba(120,200,230,0.6); color: #fff; } .mceActionPanel #insert { float: right; } /* Browse */ a.pickcolor, a.browse {text-decoration:none} a.browse span {display:block; width:20px; height:18px; border:1px solid #FFF; margin-left:1px;} .mceOldBoxModel a.browse span {width:22px; height:20px;} a.browse:hover span {border:1px solid #0A246A; background-color:#B2BBD0;} a.browse span.disabled {border:1px solid white; opacity:0.3; -ms-filter:\'alpha(opacity=30)\'; filter:alpha(opacity=30);} a.browse:hover span.disabled {border:1px solid white; background-color:transparent;} a.pickcolor span {display:block; width:20px; height:16px; margin-left:2px;} .mceOldBoxModel a.pickcolor span {width:21px; height:17px;} a.pickcolor:hover span {background-color:#B2BBD0;} div.iframecontainer {background: #fff;} /* Charmap */ table.charmap {border:1px solid #AAA; text-align:center} td.charmap, #charmap a {width:18px; height:18px; color:#000; border:1px solid #AAA; text-align:center; font-size:12px; vertical-align:middle; line-height: 18px;} #charmap a {display:block; color:#000; text-decoration:none; border:0} #charmap a:hover {background:#CCC;color:#2B6FB6} #charmap #codeN {font-size:10px; font-family:Arial,Helvetica,sans-serif; text-align:center} #charmap #codeV {font-size:40px; height:80px; border:1px solid #AAA; text-align:center} #charmap #charmapView {background-color:#fff;} /* Source */ .wordWrapCode {vertical-align:middle; border:1px none #000000; background:transparent;} .mceActionPanel {margin-top:5px;} /* Tabs classes */ .tabs {width:100%; height:19px; line-height:normal; border-bottom: 1px solid #aaa;} .tabs ul {margin:0; padding:0; list-style:none;} .tabs li {float:left; border: 1px solid #aaa; margin:0 2px 0 0; padding:0 0 0 10px; line-height:17px; height:18px; display:block;} .tabs li.current {border-bottom: 1px solid #fff; margin-right:2px;} .tabs span {float:left; display:block; padding:0px 10px 0 0;} .tabs a {text-decoration:none; font-family:Verdana, Arial; font-size:10px;} .tabs a:link, .tabs a:visited, .tabs a:hover {color:black;} .wp-core-ui #tabs { padding-bottom: 5px; background-color: transparent; } .wp-core-ui #tabs a { padding: 6px 10px; margin: 0 2px; } /* Panels */ .panel_wrapper div.panel {display:none;} .panel_wrapper div.current {display:block; width:100%; height:300px; overflow:visible;} .panel_wrapper {border:1px solid #919B9C; border-top:0px; padding:10px; padding-top:5px; clear:both; background:white;} /* Columns */ .column {float:left;} .properties {width:100%;} .properties .column1 {} .properties .column2 {text-align:left;} /* Titles */ h1, h2, h3, h4 {color:#2B6FB6; margin:0; padding:0; padding-top:5px;} h3 {font-size:14px;} .title {font-size:12px; font-weight:bold; color:#2B6FB6;} /* Dialog specific */ #link .panel_wrapper, #link div.current {height:125px;} #image .panel_wrapper, #image div.current {height:200px;} #plugintable thead {font-weight:bold; background:#DDD;} #plugintable, #about #plugintable td {border:1px solid #919B9C;} #plugintable {width:96%; margin-top:10px;} #pluginscontainer {height:290px; overflow:auto;} #colorpicker #preview {display:inline-block; padding-left:40px; height:14px; border:1px solid black; margin-left:5px; margin-right: 5px} #colorpicker #previewblock {position: relative; top: -3px; padding-left:5px; padding-top: 0px; display:inline} #colorpicker #preview_wrapper {text-align:center; padding-top:4px; white-space: nowrap; float: right;} #colorpicker #insert, #colorpicker #cancel {width: 90px} #colorpicker #colors {float:left; border:1px solid gray; cursor:crosshair;} #colorpicker #light {border:1px solid gray; margin-left:5px; float:left;width:15px; height:150px; cursor:crosshair;} #colorpicker #light div {overflow:hidden;} #colorpicker .panel_wrapper div.current {height:175px;} #colorpicker #namedcolors {width:150px;} #colorpicker #namedcolors a {display:block; float:left; width:10px; height:10px; margin:1px 1px 0 0; overflow:hidden;} #colorpicker #colornamecontainer {margin-top:5px;} #colorpicker #picker_panel fieldset {margin:auto;width:325px;} /* Localization */ body[dir="rtl"], body[dir="rtl"] fieldset, body[dir="rtl"] input, body[dir="rtl"] select, body[dir="rtl"] textarea, body[dir="rtl"] #charmap #codeN, body[dir="rtl"] .tabs a { font-family: Tahoma, sans-serif; } ' subst = '' result = str.gsub(re, subst) # Print the result of the substitution puts result

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 Ruby, please visit: http://ruby-doc.org/core-2.2.0/Regexp.html