PageSourceSearch

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Websites using lazysizes

lazysizes is a lazy loader for images and iframes driven by class names. About 177,686 websites in the PageSourceSearch index contain the code that reveals it; the 50 highest-ranked are listed below.

How is lazysizes detected?

Sites load the library from a file named lazysizes (usually lazysizes.min.js). The discovery keyword is the exact bytes PageSourceSearch looks for in every stored page and script:

lazysizes Search the index for it

A literal is matched byte for byte, case-sensitively. Combine it with another keyword, a domain, a kind or a date filter on the search page to narrow the list. About lazysizes

Top 50 websites using lazysizes

Ranked by the domain's position in the crawl's ranked list (Common Crawl harmonic centrality), highest first. view source opens the stored page or script with the match highlighted. Computed 2026-09-29 18:49:05 UTC.

#WebsiteRankFound in
1 microsoft.com 19 js https://www.microsoft.com/foxtrot/et…7a837c9a35b43038.min.js view source profile
2 harvard.edu 78 js https://www.harvard.edu/wp-content/t…a53365339086f44c55f62dc view source profile
3 cbsnews.com 134 js https://www.cbsnews.com/fly/bundles/…e6e9418524a5e7417c39ce5 view source profile
4 box.com 168 html https://www.box.com/ view source profile
5 usc.edu 235 html https://usc.edu/ view source profile
6 mit.edu 239 js https://web.mit.edu/themes/mit/assets/js/main.js?tdwlq2 view source profile
7 cloudinary.com 255 html https://cloudinary.com/pricing view source profile
8 ubuntu.com 282 html https://ubuntu.com/ view source profile
9 iheart.com 286 html https://news.iheart.com/apps/ view source profile
10 nber.org 302 html https://www.nber.org/ view source profile
11 gatech.edu 323 html https://www.gatech.edu/ view source profile
12 ncsc.gov.uk 354 js https://www.ncsc.gov.uk/themes/custo…//main-site-Bz8LHMH8.js view source profile
13 ucf.edu 411 html https://www.ucf.edu/ view source profile
14 sueddeutsche.de 524 js https://www.sueddeutsche.de/szde-ass…/js/client-BdFU2XUE.mjs view source profile
15 samsung.com 530 js https://www.samsung.com/us/smg/etc.c…b041eb9ae285ea6e3a27.js view source profile
16 inaturalist.org 544 js https://help.inaturalist.org/assets/…/scripts/bottom.js view source profile
17 theconversation.com 562 js https://cdn.theconversation.com/stat…8b56eb1988a924ace71f.js view source profile
18 instructure.com 632 html https://www.instructure.com/ view source profile
19 rt.com 661 html https://www.rt.com/ view source profile
20 csun.edu 684 html https://newsroom.csun.edu/2026/01/13…olleagues-at-nbc4-news/ view source profile
21 jotform.com 714 html https://www.jotform.com/blog/ view source profile
22 slate.com 740 html https://slate.com/ view source profile
23 ntu.edu.sg 780 js https://www.ntu.edu.sg/ResourcePacka…/scripts/main.js?v=18 view source profile
24 usu.edu 788 html https://www.usu.edu/ view source profile
25 mariadb.com 795 html https://mariadb.com/ view source profile
26 wpengine.com 883 html https://wpengine.com/blog/ view source profile
27 websta.me 955 js https://websta.me/wp-content/themes/…/js/unveil.js?ver=5.2.1 view source profile
28 hoover.org 1,006 js https://www.hoover.org/themes/hoover…/global.js?v=4.4 view source profile
29 hudl.com 1,076 html https://www.hudl.com/blog/3d-view view source profile
30 report.az 1,169 js https://report.az/assets/js/app.js?i…5544ebde9d04a36ae6f11cd view source profile
31 zshare.net 1,210 js https://www.zshare.net/wp-content/li…7c4b71f28e.js?ver=79f74 view source profile
32 leverageedu.com 1,251 html https://leverageedu.com/blog/letter-of-recommendation-lor/ view source profile
33 bylinetimes.com 1,268 html https://bylinetimes.com/ view source profile
34 girlswhocode.com 1,337 js https://girlswhocode.com/static/js/2.223205f2.chunk.js view source profile
35 okta.com 1,360 js https://www.okta.com/sites/default/f…6g9HRKq_s757_CGpnM5M.js view source profile
36 timebusinessnews.com 1,371 js https://timebusinessnews.com/wp-cont…y-load.min.js?ver=4.3.3 view source profile
37 e-architect.com 1,396 html https://www.e-architect.com/ view source profile
38 guildquality.com 1,412 html https://www.guildquality.com/ view source profile
39 techolac.com 1,435 js https://www.techolac.com/wp-content/…c5a67c89bed1b343d7bd.js view source profile
40 podbean.com 1,442 html https://www.podbean.com/ view source profile
41 grafana.com 1,461 js https://grafana.com/web/app.4835de51…ec9ee9ab1f4ba67eaad1.js view source profile
42 cetaf.org 1,472 html https://cetaf.org/ view source profile
43 ethz.ch 1,496 js https://bsse.ethz.ch/etc.clientlibs/…/clientlibs/default.js view source profile
44 sflcn.com 1,568 html https://sflcn.com/ view source profile
45 entrepreneursbreak.com 1,589 js https://entrepreneursbreak.com/wp-co…tend.min.js?ver=12.0.13 view source profile
46 newsanyway.com 1,592 js https://www.newsanyway.com/wp-conten…/lazyload.js?ver=10.3.2 view source profile
47 techgyd.com 1,609 html https://www.techgyd.com/ view source profile
48 wufoo.com 1,625 html https://www.wufoo.com/ view source profile
49 marketsandmarkets.com 1,669 html https://www.marketsandmarkets.com/ view source profile
50 igeekphone.com 1,743 js https://www.igeekphone.com/wp-conten…/lazyload.js?ver=9.2.0 view source profile

How it appears in the source

From microsoft.com (js):

applyUhfLayoutContainerId);   } else {     applyUhfLayoutContainerId();   } })(document);  /*! lazysizes - v5.3.2 */  !function(e){var t=function(u,D,f){"use strict";var k,H;if(function(){var e;var t=

See every site: search for lazysizes

Questions about finding lazysizes

How does PageSourceSearch know a website uses lazysizes?
By the source itself: Sites load the library from a file named lazysizes (usually lazysizes.min.js). PageSourceSearch stores the raw HTML and first-party JavaScript of each crawled site and matches the keyword byte for byte, so every listed site's stored source contains it.
Is this a complete list of websites using lazysizes?
No. The page lists the 50 highest-ranked sites in the index whose source holds the keyword, out of about 177,686 websites that do; the count is the index's estimate at the time the list was computed. Run the keyword as a search to page through all of them, or add a kind or date filter.
How do I find websites that use lazysizes together with another technology?
Search for both keywords at once: several terms separated by spaces must all be found on the same site, or with the Same page toggle in the same page. For example lazysizes with wp-content/plugins/ lists the WordPress sites that use lazysizes.