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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

r"
"
gm

Test String

Code Generator

Generated Code

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(?m)<a class=\"Anchor-qkwhxv-0 cRgrlM\" href=\"([^\"]+)\"`) var str = `<div class="LoadMoreWrapper__Container-hxv6br-0 rnteU" id="00000142-9228-d1f0-a5c6-b2fd817d0000" name="cybersecurity" spacing="6"><p class="sc-bdVaJa iEuuK">The Latest</p><div class="ntx-mediaobject-container"><div class="jpvx17-0-Box-cwadsP eISNqp" spacing="5"><div class="jpvx17-0-Box-cwadsP gfFbpn"><h3 class="sc-bdVaJa ixAtVd"><a class="Anchor-qkwhxv-0 cRgrlM" href="https://money.usnews.com/money/personal-finance/family-finance/articles/2018-06-22/10-things-to-do-immediately-after-your-identity-is-stolen" letter-spacing="0.6">10 Things to Do If Your Identity Is Stolen</a></h3><p class="Hide-l1npyw-0 iLzjOL Paragraph-fqygwe-0 foOETH" size="3" spacing="4">Think someone has your personal information? Take these steps to protect yourself.</p><p class="Hide-l1npyw-0 iLzjOL fqygwe-0-Paragraph-hHEPzZ ggYInA" size="2"><span class="aabx0k-0-Span-juOiwt bplooz" size="2"><span class="aabx0k-0-Span-juOiwt jQyjzQ" size="2"><span></span>Maryalene LaPonsie</span></span><span> <!-- -->June 22, 2018</span></p></div><div class="jpvx17-0-Box-cwadsP eWPQPg"><a class="Anchor-qkwhxv-0 iRvSIy" href="https://money.usnews.com/money/personal-finance/family-finance/articles/2018-06-22/10-things-to-do-immediately-after-your-identity-is-stolen" letter-spacing="0.6"><picture class="Image__Picture-s1o4eta-0 dHmORe"><source srcset="https://www.usnews.com/dims4/USNEWS/11b477b/2147483647/crop/500x333%2B0%2B0/resize/303x202/quality/85/?url=http%3A%2F%2Fmedia.beam.usnews.com%2Ffb%2F7e%2Fc95bd58f4c8b9f21b7696e907e8d%2Fresizes%2F500%2F150731-identitystolen-stock.jpg" media="(min-width: 640px)"><img src="https://www.usnews.com/dims4/USNEWS/cc27d02/2147483647/crop/333x333%2B74%2B0/resize/84x84/quality/85/?url=http%3A%2F%2Fmedia.beam.usnews.com%2Ffb%2F7e%2Fc95bd58f4c8b9f21b7696e907e8d%2Fresizes%2F500%2F150731-identitystolen-stock.jpg" class="MediaObject__MediaImage-qwnn1d-0 gkjlrf Image-s1o4eta-2 jloNmB"></picture></a></div></div><div class="jpvx17-0-Box-cwadsP eISNqp" spacing="5"><div class="jpvx17-0-Box-cwadsP gfFbpn"><h3 class="sc-bdVaJa ixAtVd"><a class="Anchor-qkwhxv-0 cRgrlM" href="https://www.usnews.com/news/best-states/nevada/articles/2018-06-01/cybersecurity-education-growing-in-nevada-as-risks-increase" letter-spacing="0.6">Cybersecurity Education Growing in Nevada as Risks Increase</a></h3><p class="Hide-l1npyw-0 iLzjOL Paragraph-fqygwe-0 foOETH" size="3" spacing="4">Those who step into this virtual world will face thieving cyber gangs who are on the hunt for electronic bikes in Europe.</p><p class="Hide-l1npyw-0 iLzjOL fqygwe-0-Paragraph-hHEPzZ ggYInA" size="2"><span class="aabx0k-0-Span-juOiwt bplooz" size="2"><span class="aabx0k-0-Span-juOiwt jQyjzQ" size="2"><span></span>Associated Press</span></span><span> <!-- -->June 1, 2018</span></p></div><div class="jpvx17-0-Box-cwadsP eWPQPg"><a class="Anchor-qkwhxv-0 iRvSIy" href="https://www.usnews.com/news/best-states/nevada/articles/2018-06-01/cybersecurity-education-growing-in-nevada-as-risks-increase" letter-spacing="0.6"><picture class="Image__Picture-s1o4eta-0 dHmORe"><source srcset="https://www.usnews.com/dims4/USNEWS/fb9d276/2147483647/thumbnail/303x202/quality/85/?url=http%3A%2F%2Fmedia.beam.usnews.com%2F40%2F1dbb0f2ec0ba0b3e6aa6e523ad2ac5%2Fresizes%2F500%2Fmedia%3A529eea2ecbd644b3a52e9865c09ede2dExchange_Cybersecurity_Education_67549.jpg" media="(min-width: 640px)"><img src="https://www.usnews.com/dims4/USNEWS/a254de6/2147483647/thumbnail/84x84/quality/85/?url=http%3A%2F%2Fmedia.beam.usnews.com%2F40%2F1dbb0f2ec0ba0b3e6aa6e523ad2ac5%2Fresizes%2F500%2Fmedia%3A529eea2ecbd644b3a52e9865c09ede2dExchange_Cybersecurity_Education_67549.jpg" class="MediaObject__MediaImage-qwnn1d-0 gkjlrf Image-s1o4eta-2 jloNmB"></picture></a></div></div><div class="Hide-l1npyw-0 BSIOt jpvx17-0-Box-cwadsP kicwrf" type="rect_" spacing="5"><div id="ad" class="ad " data-ad-type="rect_" data-dimensions="300x250,300x600" data-targeting="{}"></div></div><div class="Hide-l1npyw-0 biIYek jpvx17-0-Box-cwadsP bVnTJr" type="lb_" spacing="5"><div id="ad" class="ad " data-ad-type="lb_" data-dimensions="728x90" data-targeting="{}"></div></div><div class="jpvx17-0-Box-cwadsP eISNqp" spacing="5"><div class="jpvx17-0-Box-cwadsP gfFbpn"><h3 class="sc-bdVaJa ixAtVd"><a class="Anchor-qkwhxv-0 cRgrlM" href="https://www.usnews.com/news/healthcare-of-tomorrow/articles/2018-05-25/security-of-medical-devices-is-latest-health-care-concern" letter-spacing="0.6">Can a Hospital Room Be Hacked?</a></h3><p class="Hide-l1npyw-0 iLzjOL Paragraph-fqygwe-0 foOETH" size="3" spacing="4">Cyberattacks on medical devices could mean myriad problems for hospitals and other health care providers.</p><p class="Hide-l1npyw-0 iLzjOL fqygwe-0-Paragraph-hHEPzZ ggYInA" size="2"><span class="aabx0k-0-Span-juOiwt bplooz" size="2"><span class="aabx0k-0-Span-juOiwt jQyjzQ" size="2"><span></span>Terena Bell</span></span><span> <!-- -->May 25, 2018</span></p></div><div class="jpvx17-0-Box-cwadsP eWPQPg"><a class="Anchor-qkwhxv-0 iRvSIy" href="https://www.usnews.com/news/healthcare-of-tomorrow/articles/2018-05-25/security-of-medical-devices-is-latest-health-care-concern" letter-spacing="0.6"><picture class="Image__Picture-s1o4eta-0 dHmORe"><source srcset="https://www.usnews.com/dims4/USNEWS/c7a4da6/2147483647/thumbnail/303x202/quality/85/?url=http%3A%2F%2Fmedia.beam.usnews.com%2F73%2F980b3f4f4eb7fcf9bf8df3cae5907b%2F45876FE_PR_080913_Emptyhospitalroom.jpg" media="(min-width: 640px)"><img src="https://www.usnews.com/dims4/USNEWS/43bd6e9/2147483647/thumbnail/84x84/quality/85/?url=http%3A%2F%2Fmedia.beam.usnews.com%2F73%2F980b3f4f4eb7fcf9bf8df3cae5907b%2F45876FE_PR_080913_Emptyhospitalroom.jpg" class="MediaObject__MediaImage-qwnn1d-0 gkjlrf Image-s1o4eta-2 jloNmB"></picture></a></div></div><div class="jpvx17-0-Box-cwadsP eISNqp" spacing="5"><div class="jpvx17-0-Box-cwadsP gfFbpn"><h3 class="sc-bdVaJa ixAtVd"><a class="Anchor-qkwhxv-0 cRgrlM" href="https://www.usnews.com/news/best-countries/articles/2018-05-24/data-heavy-reliance-on-social-media-aligns-with-trust-in-private-companies" letter-spacing="0.6">Who Will Fix Internet Privacy Problems? </a></h3><p class="Hide-l1npyw-0 iLzjOL Paragraph-fqygwe-0 foOETH" size="3" spacing="4">New and unprecedented European Union internet rules may still be insufficient at a time of deep privacy concerns globally.</p><p class="Hide-l1npyw-0 iLzjOL fqygwe-0-Paragraph-hHEPzZ ggYInA" size="2"><span class="aabx0k-0-Span-juOiwt bplooz" size="2"><span class="aabx0k-0-Span-juOiwt jQyjzQ" size="2"><span></span>Paul D. Shinkman</span></span><span> <!-- -->May 24, 2018</span></p></div><div class="jpvx17-0-Box-cwadsP eWPQPg"><a class="Anchor-qkwhxv-0 iRvSIy" href="https://www.usnews.com/news/best-countries/articles/2018-05-24/data-heavy-reliance-on-social-media-aligns-with-trust-in-private-companies" letter-spacing="0.6"><picture class="Image__Picture-s1o4eta-0 dHmORe"><source srcset="https://www.usnews.com/dims4/USNEWS/884107c/2147483647/crop/494x329%2B0%2B0/resize/303x202/quality/85/?url=http%3A%2F%2Fmedia.beam.usnews.com%2F1b%2F91%2Fc4cc2d5e4f5e8a19ecbff43a7419%2Fresizes%2F500%2F180524-euprivacy-editorial.jpg" media="(min-width: 640px)"><img src="https://www.usnews.com/dims4/USNEWS/7c4a0a1/2147483647/crop/329x329%2B0%2B0/resize/84x84/quality/85/?url=http%3A%2F%2Fmedia.beam.usnews.com%2F1b%2F91%2Fc4cc2d5e4f5e8a19ecbff43a7419%2Fresizes%2F500%2F180524-euprivacy-editorial.jpg" class="MediaObject__MediaImage-qwnn1d-0 gkjlrf Image-s1o4eta-2 jloNmB"></picture></a></div></div><div class="jpvx17-0-Box-cwadsP eISNqp" spacing="5"><div class="jpvx17-0-Box-cwadsP gfFbpn"><h3 class="sc-bdVaJa ixAtVd"><a class="Anchor-qkwhxv-0 cRgrlM" href="https://money.usnews.com/money/personal-finance/family-finance/articles/2018-05-22/how-to-protect-yourself-from-medical-identity-theft" letter-spacing="0.6">Protect Yourself From Medical ID Theft</a></h3><p class="Hide-l1npyw-0 iLzjOL Paragraph-fqygwe-0 foOETH" size="3" spacing="4">A thief who uses your medical data to access treatment could harm your finances – and your health.</p><p class="Hide-l1npyw-0 iLzjOL fqygwe-0-Paragraph-hHEPzZ ggYInA" size="2"><span class="aabx0k-0-Span-juOiwt bplooz" size="2"><span class="aabx0k-0-Span-juOiwt jQyjzQ" size="2"><span></span>Susannah Snider</span></span><span> <!-- -->May 22, 2018</span></p></div><div class="jpvx17-0-Box-cwadsP eWPQPg"><a class="Anchor-qkwhxv-0 iRvSIy" href="https://money.usnews.com/money/personal-finance/family-finance/articles/2018-05-22/how-to-protect-yourself-from-medical-identity-theft" letter-spacing="0.6"><picture class="Image__Picture-s1o4eta-0 dHmORe"><source srcset="https://www.usnews.com/dims4/USNEWS/0858209/2147483647/thumbnail/303x202/quality/85/?url=http%3A%2F%2Fmedia.beam.usnews.com%2Fd2%2Ff9%2F351f0de446549f8131aefe62bddd%2Fresizes%2F500%2F140605-medicalrecords-stock.jpg" media="(min-width: 640px)"><img src="https://www.usnews.com/dims4/USNEWS/34458ff/2147483647/thumbnail/84x84/quality/85/?url=http%3A%2F%2Fmedia.beam.usnews.com%2Fd2%2Ff9%2F351f0de446549f8131aefe62bddd%2Fresizes%2F500%2F140605-medicalrecords-stock.jpg" class="MediaObject__MediaImage-qwnn1d-0 gkjlrf Image-s1o4eta-2 jloNmB"></picture></a></div></div><div class="jpvx17-0-Box-cwadsP eISNqp" spacing="5"><div class="jpvx17-0-Box-cwadsP gfFbpn"><h3 class="sc-bdVaJa ixAtVd"><a class="Anchor-qkwhxv-0 cRgrlM" href="https://money.usnews.com/investing/cryptocurrency/articles/2018-05-04/is-bitcoin-a-safe-investment" letter-spacing="0.6">Is Bitcoin a Safe Investment?</a></h3><p class="Hide-l1npyw-0 iLzjOL Paragraph-fqygwe-0 foOETH" size="3" spacing="4">The frequent hacking of cryptocurrency exchanges serves as a warning to investors.</p><p class="Hide-l1npyw-0 iLzjOL fqygwe-0-Paragraph-hHEPzZ ggYInA" size="2"><span class="aabx0k-0-Span-juOiwt bplooz" size="2"><span class="aabx0k-0-Span-juOiwt jQyjzQ" size="2"><span></span>Ellen Chang</span></span><span> <!-- -->May 4, 2018</span></p></div><div class="jpvx17-0-Box-cwadsP eWPQPg"><a class="Anchor-qkwhxv-0 iRvSIy" href="https://money.usnews.com/investing/cryptocurrency/articles/2018-05-04/is-bitcoin-a-safe-investment" letter-spacing="0.6"><picture class="Image__Picture-s1o4eta-0 dHmORe"><source srcset="https://www.usnews.com/dims4/USNEWS/d4ebfeb/2147483647/thumbnail/303x202/quality/85/?url=http%3A%2F%2Fmedia.beam.usnews.com%2F93%2Fce%2Fac58f43b4ee2911a2a4bf03ae19d%2Fresizes%2F500%2F180504-bitcoin-stock.jpg" media="(min-width: 640px)"><img src="https://www.usnews.com/dims4/USNEWS/b70a2ec/2147483647/thumbnail/84x84/quality/85/?url=http%3A%2F%2Fmedia.beam.usnews.com%2F93%2Fce%2Fac58f43b4ee2911a2a4bf03ae19d%2Fresizes%2F500%2F180504-bitcoin-stock.jpg" class="MediaObject__MediaImage-qwnn1d-0 gkjlrf Image-s1o4eta-2 jloNmB"></picture></a></div></div><div class="jpvx17-0-Box-cwadsP eISNqp" spacing="5"><div class="jpvx17-0-Box-cwadsP gfFbpn"><h3 class="sc-bdVaJa ixAtVd"><a class="Anchor-qkwhxv-0 cRgrlM" href="https://money.usnews.com/investing/investing-101/articles/2017-11-06/best-bitcoin-wallet-of-2018" letter-spacing="0.6">The Best Bitcoin Wallet of 2018</a></h3><p class="Hide-l1npyw-0 iLzjOL Paragraph-fqygwe-0 foOETH" size="3" spacing="4">Storing Bitcoin is just as important as buying it. With a wealth of options available, which is best?</p><p class="Hide-l1npyw-0 iLzjOL fqygwe-0-Paragraph-hHEPzZ ggYInA" size="2"><span class="aabx0k-0-Span-juOiwt bplooz" size="2"><span class="aabx0k-0-Span-juOiwt jQyjzQ" size="2"><span></span>John Divine</span></span><span> <!-- -->May 3, 2018</span></p></div><div class="jpvx17-0-Box-cwadsP eWPQPg"><a class="Anchor-qkwhxv-0 iRvSIy" href="https://money.usnews.com/investing/investing-101/articles/2017-11-06/best-bitcoin-wallet-of-2018" letter-spacing="0.6"><picture class="Image__Picture-s1o4eta-0 dHmORe"><source srcset="https://www.usnews.com/dims4/USNEWS/a64643a/2147483647/crop/500x333%2B0%2B0/resize/303x202/quality/85/?url=http%3A%2F%2Fmedia.beam.usnews.com%2F7f%2F38%2F697a1842489ba9834f10d7bd7464%2Fresizes%2F500%2F160610-bitcoin-stock.jpg" media="(min-width: 640px)"><img src="https://www.usnews.com/dims4/USNEWS/5857c9f/2147483647/crop/333x333%2B148%2B0/resize/84x84/quality/85/?url=http%3A%2F%2Fmedia.beam.usnews.com%2F7f%2F38%2F697a1842489ba9834f10d7bd7464%2Fresizes%2F500%2F160610-bitcoin-stock.jpg" class="MediaObject__MediaImage-qwnn1d-0 gkjlrf Image-s1o4eta-2 jloNmB"></picture></a></div></div><div class="Hide-l1npyw-0 BSIOt jpvx17-0-Box-cwadsP kicwrf" type="rect_" spacing="5"><div id="ad" class="ad " data-ad-type="rect_" data-dimensions="300x250,300x600" data-targeting="{}"></div></div><div class="Hide-l1npyw-0 biIYek jpvx17-0-Box-cwadsP bVnTJr" type="lb_" spacing="5"><div id="ad" class="ad " data-ad-type="lb_" data-dimensions="728x90" data-targeting="{}"></div></div><div class="jpvx17-0-Box-cwadsP eISNqp" spacing="5"><div class="jpvx17-0-Box-cwadsP gfFbpn"><h3 class="sc-bdVaJa ixAtVd"><a class="Anchor-qkwhxv-0 cRgrlM" href="https://money.usnews.com/money/personal-finance/family-finance/articles/2018-04-17/4-ways-millennials-can-avoid-online-financial-scams" letter-spacing="0.6">Millennials: 4 Ways to Avoid Money Scams</a></h3><p class="Hide-l1npyw-0 iLzjOL Paragraph-fqygwe-0 foOETH" size="3" spacing="4">A new FTC report shows millennials are more likely to fall for fraud than older generations.</p><p class="Hide-l1npyw-0 iLzjOL fqygwe-0-Paragraph-hHEPzZ ggYInA" size="2"><span class="aabx0k-0-Span-juOiwt bplooz" size="2"><span class="aabx0k-0-Span-juOiwt jQyjzQ" size="2"><span></span>Geoff Williams</span></span><span> <!-- -->April 17, 2018</span></p></div><div class="jpvx17-0-Box-cwadsP eWPQPg"><a class="Anchor-qkwhxv-0 iRvSIy" href="https://money.usnews.com/money/personal-finance/family-finance/articles/2018-04-17/4-ways-millennials-can-avoid-online-financial-scams" letter-spacing="0.6"><picture class="Image__Picture-s1o4eta-0 dHmORe"><source srcset="https://www.usnews.com/dims4/USNEWS/4a6ff8c/2147483647/thumbnail/303x202/quality/85/?url=http%3A%2F%2Fmedia.beam.usnews.com%2Feb%2F20%2F3b257d834375b4d600b264fc9e93%2Fresizes%2F500%2F180417-upsetmillennialworker-stock.jpg" media="(min-width: 640px)"><img src="https://www.usnews.com/dims4/USNEWS/87337cc/2147483647/thumbnail/84x84/quality/85/?url=http%3A%2F%2Fmedia.beam.usnews.com%2Feb%2F20%2F3b257d834375b4d600b264fc9e93%2Fresizes%2F500%2F180417-upsetmillennialworker-stock.jpg" class="MediaObject__MediaImage-qwnn1d-0 gkjlrf Image-s1o4eta-2 jloNmB"></picture></a></div></div><div class="jpvx17-0-Box-cwadsP eISNqp" spacing="5"><div class="jpvx17-0-Box-cwadsP gfFbpn"><h3 class="sc-bdVaJa ixAtVd"><a class="Anchor-qkwhxv-0 cRgrlM" href="https://www.usnews.com/news/national-news/articles/2018-04-13/can-the-law-stop-ransomware" letter-spacing="0.6">Can the Law Stop Ransomware?</a></h3><p class="Hide-l1npyw-0 iLzjOL Paragraph-fqygwe-0 foOETH" size="3" spacing="4">Lawmakers across the U.S. have made even the possession of malware illegal – whether that will deter attacks, however, is a different story.</p><p class="Hide-l1npyw-0 iLzjOL fqygwe-0-Paragraph-hHEPzZ ggYInA" size="2"><span class="aabx0k-0-Span-juOiwt bplooz" size="2"><span class="aabx0k-0-Span-juOiwt jQyjzQ" size="2"><span></span>Alan Neuhauser</span></span><span> <!-- -->April 13, 2018</span></p></div><div class="jpvx17-0-Box-cwadsP eWPQPg"><a class="Anchor-qkwhxv-0 iRvSIy" href="https://www.usnews.com/news/national-news/articles/2018-04-13/can-the-law-stop-ransomware" letter-spacing="0.6"><picture class="Image__Picture-s1o4eta-0 dHmORe"><source srcset="https://www.usnews.com/dims4/USNEWS/532da2a/2147483647/thumbnail/303x202/quality/85/?url=http%3A%2F%2Fmedia.beam.usnews.com%2F90%2Fe0%2F7c4249154b4680068bd0e1ba6d3a%2Fresizes%2F500%2F180410-ransomeware-editorial.jpg" media="(min-width: 640px)"><img src="https://www.usnews.com/dims4/USNEWS/87a73a7/2147483647/thumbnail/84x84/quality/85/?url=http%3A%2F%2Fmedia.beam.usnews.com%2F90%2Fe0%2F7c4249154b4680068bd0e1ba6d3a%2Fresizes%2F500%2F180410-ransomeware-editorial.jpg" class="MediaObject__MediaImage-qwnn1d-0 gkjlrf Image-s1o4eta-2 jloNmB"></picture></a></div></div></div><button class="s10zmu5c-0-Button-kDSBcD hUlYdQ"><div class="button-content">Load More</div></button></div>` for i, match := range re.FindAllString(str, -1) { fmt.Println(match, "found at index", i) } }

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 Golang, please visit: https://golang.org/pkg/regexp/