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

/
/
g

Test String

Code Generator

Language

Generated Code

const regex = /£\d+\.\d{1,2}/g; // Alternative syntax using RegExp constructor // const regex = new RegExp('£\\d+\\.\\d{1,2}', 'g') const str = `<div style="float:left;"><a class="url" href="http://www.amazon.co.uk/AllThingsAccessory%C2%AE-Sports-Running-Jogging-... src="http://ecx.images-amazon.com/images/I/51bQWjrCioL._SL160_.jpg" alt="AllThingsAccessory Sports" border="0" hspace="0" vspace="0" /></a></div><span class="riRssTitle"><a href="http://www.amazon.co.uk/AllThingsAccessory%C2%AE-Sports-Running-Jogging-...® Sports Running Jogging Gym Armband Arm Band Case Cover Holder For iPhone 6 5 5S 5C 4S 4</a></span> <br /><span class="riRssContributor">AllThingsAccessory®</span> <br /><img src="http://g-ecx.images-amazon.com/images/G/02/x-locale/common/icons/uparrow... width="13" align="abstop" alt="Ranking has gone up in the past 24 hours" title="Ranking has gone up in the past 24 hours" height="11" border="0" /> <font color="green"><strong>52,006%</strong></font> Sales Rank in Sports & Outdoors: 50 (was 26,053 yesterday) <br /> <img src="http://g-ecx.images-amazon.com/images/G/02/detail/stars-4-5._V192253866_... width="64" height="12" border="0" style="margin: 0; padding: 0;"/>(51)<br /><br /><a href="http://www.amazon.co.uk/AllThingsAccessory%C2%AE-Sports-Running-Jogging-... new: </a> <strike>£7.99 - £9.99</strike> <font color="#990000"><b>£4.99</b></font> <br /><br />(Visit the <a href="http://www.amazon.co.uk/gp/movers-and-shakers/sports/ref=pd_zg_rss_ms_sg... & Shakers in Sports & Outdoors</a> list for authoritative information on this product's current rank.)`; // 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