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

/
/
gi

Test String

Code Generator

Language

Generated Code

const regex = /\"ou\"\:\"(https?:\/\/.*\.(?:png|jpg|jpeg|gif))/gi; // Alternative syntax using RegExp constructor // const regex = new RegExp('\\"ou\\"\\:\\"(https?:\\\/\\\/.*\\.(?:png|jpg|jpeg|gif))', 'gi') const str = `{"cb":21,"cl":3,"cr":3,"ct":21,"id":"dW5GZvKh_3M_2M:","isu":"www8.hp.com","itg":false,"ity":"png","oh":356,"ou":"http://product-images.www8-hp.com/digmedialib/prodimg/lowres/c03235671.png","ow":474} {"cb":21,"ct":21,"id":"9br0fx79WphEoM:","isu":"centrecom.com.au","itg":false,"ity":"jpeg","oh":400,"ou":"https://centrecomstatic.s3.amazonaws.com/images/upload/0015329_0.jpeg","ow":400} {"cb":21,"cl":3,"cr":3,"ct":21,"id":"JhRyJSH9KgtexM:","isu":"www8.hp.com","itg":false,"ity":"png","oh":356,"ou":"http://product-images.www8-hp.com/digmedialib/prodimg/lowres/c03235691.png","ow":474} {"cb":21,"cl":3,"cr":3,"ct":21,"id":"r0jI0V0ECpUxCM:","isu":"www8.hp.com","itg":false,"ity":"png","oh":356,"ou":"http://product-images.www8-hp.com/digmedialib/prodimg/lowres/c03235770.png","ow":474} {"ct":3,"id":"ySkYQ0zkDOWQaM:","isu":"amazon.com","itg":false,"ity":"jpg","oh":524,"ou":"https://images-na.ssl-images-amazon.com/images/I/715CMBwfmtL._SL1500_.jpg","ow":1500} {"cl":3,"cr":3,"id":"4XMWsfu3vQSwcM:","isu":"geb.ebay.in","itg":false,"ity":"jpg","oh":354,"ou":"http://i.ebayimg.com/00/s/NjQxWDkwNQ\\u003d\\u003d/z/vD0AAOSwyQtVm-3Z/\$_12.JPG?set_id\\u003d880000500F","ow":500} {"cb":3,"cl":3,"ct":3,"id":"nl8KfxeJ1X1X1M:","isu":"argep.hu","itg":false,"ity":"jpg","oh":239,"ou":"http://www.usanotebook.hu/termekek/HP-Compaq-NB-USB-3.0-port-replikator-3005pr-32216A.jpg","ow":550}`; // 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