Third Party Web

Check out the shiny new web UI https://www.thirdpartyweb.today/

Data on third party entities and their impact on the web.

This document is a summary of which third party scripts are most responsible for excessive JavaScript execution on the web today.

Table of Contents

1. Goals
2. Methodology
3. npm Module
4. Updates
5. Data
   1. Summary
   2. How to Interpret
   3. Third Parties by Category
      1. Advertising
      2. Analytics
      3. Social
      4. Video
      5. Developer Utilities
      6. Hosting Platforms
      7. Marketing
      8. Customer Success
      9. Content & Publishing
      10. CDNs
      11. Tag Management
      12. Consent Management Provider
      13. Mixed / Other
   4. Third Parties by Total Impact
6. Future Work
7. FAQs
8. Contributing

Goals

1. Quantify the impact of third party scripts on the web.
2. Identify the third party scripts on the web that have the greatest performance cost.
3. Give developers the information they need to make informed decisions about which third parties to include on their sites.
4. Incentivize responsible third party script behavior.
5. Make this information accessible and useful.

Methodology

HTTP Archive is an initiative that tracks how the web is built. Every month, ~4 million sites are crawled with Lighthouse on mobile. Lighthouse breaks down the total script execution time of each page and attributes the execution to a URL. Using BigQuery, this project aggregates the script execution to the origin-level and assigns each origin to the responsible entity.

npm Module

The entity classification data is available as an npm module.

const {getEntity} = require('third-party-web')
const entity = getEntity('https://d36mpcpuzc4ztk.cloudfront.net/js/visitor.js')
console.log(entity)
//   {
//     "name": "Freshdesk",
//     "homepage": "https://freshdesk.com/",
//     "category": "customer-success",
//     "domains": ["d36mpcpuzc4ztk.cloudfront.net"]
//   }

Updates

2021-01-01 dataset

Due to a change in HTTPArchive measurement which temporarily disabled site-isolation (out-of-process iframes), all of the third-parties whose work previously took place off the main-thread are now counted on the main thread (and thus appear in our stats). This is most evident in the change to Google-owned properties such as YouTube and Doubleclick whose complete cost are now captured.

2019-05-13 dataset

A shortcoming of the attribution approach has been fixed. Total usage is now reported based on the number of pages in the dataset that use the third-party, not the number of scripts. Correspondingly, all average impact times are now reported per page rather than per script. Previously, a third party could appear to have a lower impact or be more popular simply by splitting their work across multiple files.

Third-parties that performed most of their work from a single script should see little to no impact from this change, but some entities have seen significant ranking movement. Hosting providers that host entire pages are, understandably, the most affected.

Some notable changes below:

Third-Party	Previously (per-script)	Now (per-page)
Beeketing	137 ms	465 ms
Sumo	263 ms	798 ms
Tumblr	324 ms	1499 ms
Yandex APIs	393 ms	1231 ms
Google Ads	402 ms	1285 ms
Wix	972 ms	5393 ms

2019-05-06 dataset

Google Ads clarified that www.googletagservices.com serves more ad scripts than generic tag management, and it has been reclassified accordingly. This has dropped the overall Tag Management share considerably back down to its earlier position.

2019-03-01 dataset

Almost 2,000 entities tracked now across ~3,000+ domains! Huge props to @simonhearne for making this massive increase possible. Tag Managers have now been split out into their own category since they represented such a large percentage of the "Mixed / Other" category.

2019-02-01 dataset

Huge props to WordAds for reducing their impact from ~2.5s to ~200ms on average! A few entities are showing considerably less data this cycle (Media Math, Crazy Egg, DoubleVerify, Bootstrap CDN). Perhaps they've added new CDNs/hostnames that we haven't identified or the basket of sites in HTTPArchive has shifted away from their usage.

Data

Summary

Across top ~4 million sites, ~2700 origins account for ~57% of all script execution time with the top 50 entities already accounting for ~47%. Third party script execution is the majority chunk of the web today, and it's important to make informed choices.

How to Interpret

Each entity has a number of data points available.

1. Usage (Total Number of Occurrences) - how many scripts from their origins were included on pages
2. Total Impact (Total Execution Time) - how many seconds were spent executing their scripts across the web
3. Average Impact (Average Execution Time) - on average, how many milliseconds were spent executing each script
4. Category - what type of script is this

Third Parties by Category

This section breaks down third parties by category. The third parties in each category are ranked from first to last based on the average impact of their scripts. Perhaps the most important comparisons lie here. You always need to pick an analytics provider, but at least you can pick the most well-behaved analytics provider.

Overall Breakdown

Unsurprisingly, ads account for the largest identifiable chunk of third party script execution.

Advertising

These scripts are part of advertising networks, either serving or measuring.

Rank	Name	Usage	Average Impact
1	Tapad	12,636	5 ms
2	Bidswitch	77,534	5 ms
3	EQ works	24,776	5 ms
4	AdGear	28,832	5 ms
5	Sonobi	105,377	5 ms
6	TripleLift	115,519	5 ms
7	Unruly Media	10,955	6 ms
8	Crimtan	96,585	6 ms
9	adKernel	40,746	6 ms
10	DeepIntent	73,341	7 ms
11	iPROM	83,515	7 ms
12	33 Across	132,626	8 ms
13	Sharethrough	35,867	9 ms
14	Beachfront Media	22,212	9 ms
15	ContextWeb	41,772	9 ms
16	ucfunnel ucX	9,958	9 ms
17	Yieldmo	46,302	10 ms
18	Tribal Fusion	173,400	11 ms
19	OpenX	215,967	12 ms
20	Delta Projects AB	17,117	15 ms
21	OneTag	141,217	25 ms
22	Teads	83,835	30 ms
23	RTB House AdPilot	15,343	32 ms
24	Onfocus	13,630	32 ms
25	LoopMe	61,818	42 ms
26	Constant Contact	18,609	49 ms
27	AppNexus	192,000	56 ms
28	Adform	51,641	66 ms
29	Index Exchange	193,085	79 ms
30	GumGum	147,038	88 ms
31	Simpli.fi	20,301	89 ms
32	LinkedIn Ads	189,262	89 ms
33	SiteScout	11,380	92 ms
34	STINGRAY	22,073	93 ms
35	MailMunch	26,938	94 ms
36	Scorecard Research	39,311	96 ms
37	Media Math	12,324	98 ms
38	Reklama	5,764	98 ms
39	StackAdapt	11,682	103 ms
40	ID5 Identity Cloud	78,299	105 ms
41	ActiveCampaign	32,289	109 ms
42	F@N Communications	5,567	109 ms
43	Twitter Online Conversion Tracking	107,645	112 ms
44	Affiliate Window	7,054	114 ms
45	The Trade Desk	41,175	114 ms
46	sovrn	74,072	122 ms
47	Branch Metrics	17,919	124 ms
48	BlueCava	7,375	142 ms
49	Yahoo!	26,268	145 ms
50	Outbrain	66,714	151 ms
51	Eyeota	25,443	157 ms
52	Amazon Ads	295,346	173 ms
53	Gemius	34,117	194 ms
54	DTSCOUT	52,864	199 ms
55	BlueKai	99,102	201 ms
56	LINE Corporation	30,410	202 ms
57	OwnerIQ	13,961	213 ms
58	AudienceSearch	63,098	214 ms
59	Simplicity Marketing	9,187	225 ms
60	Bing Ads	60,072	230 ms
61	Smart AdServer	69,072	251 ms
62	Unbounce	10,185	252 ms
63	Between Digital	6,284	259 ms
64	Quora Ads	6,400	285 ms
65	fluct	27,604	294 ms
66	Criteo	253,709	323 ms
67	Tynt	172,762	324 ms
68	Technorati	89,172	347 ms
69	i-mobile	15,890	368 ms
70	IPONWEB	33,059	377 ms
71	Geniee	23,506	379 ms
72	Adroll	35,751	385 ms
73	VigLink	50,677	403 ms
74	Crowd Control	91,065	423 ms
75	Skimbit	95,914	453 ms
76	Rubicon Project	278,207	471 ms
77	Supership	20,178	531 ms
78	Yandex Ads	17,572	626 ms
79	Yahoo! JAPAN Ads	78,117	629 ms
80	Infolinks	55,394	663 ms
81	Klaviyo	123,185	669 ms
82	TrafficStars	12,308	698 ms
83	Moat	15,290	715 ms
84	Privy	24,457	718 ms
85	Integral Ad Science	25,510	725 ms
86	AdScore	5,798	761 ms
87	Taboola	47,105	802 ms
88	LongTail Ad Solutions	8,471	975 ms
89	OptiMonk	10,355	1063 ms
90	Cxense	5,410	1137 ms
91	Attentive	9,725	1142 ms
92	Media.net	126,029	1286 ms
93	Pubmatic	309,062	1633 ms
94	WordAds	105,042	1792 ms
95	MGID	10,762	2259 ms
96	Sizmek	6,979	2370 ms
97	Google/Doubleclick Ads	1,696,595	2417 ms
98	Connatix	12,943	3858 ms
99	Mediavine	9,994	4061 ms
100	Bridgewell DSP	22,900	4329 ms

Analytics

These scripts measure or track users and their actions. There's a wide range in impact here depending on what's being tracked.

Rank	Name	Usage	Average Impact
1	Pingdom RUM	3,799	60 ms
2	SpeedCurve LUX	2,501	65 ms
3	WordPress Site Stats	250,050	67 ms
4	Alexa	4,749	70 ms
5	Fastest Forward	3,067	75 ms
6	Sailthru	6,674	82 ms
7	Ekm Systems	1,625	84 ms
8	Roxr Software	18,081	105 ms
9	Woopra	2,215	106 ms
10	LiveRamp IdentityLink	14,613	114 ms
11	Smartlook	2,888	117 ms
12	Movable Ink	1,713	123 ms
13	Conversant	56,953	124 ms
14	Polldaddy	4,510	128 ms
15	StatCounter	62,405	131 ms
16	XiTi	3,040	133 ms
17	GoSquared	1,498	134 ms
18	Treasure Data	16,424	141 ms
19	Site24x7 Real User Monitoring	1,000	141 ms
20	Quantcast	135,222	147 ms
21	Brandmetrics	2,492	147 ms
22	Okta	3,556	163 ms
23	UpSellit	1,107	179 ms
24	Stamped.io	13,390	180 ms
25	Fastly Insights	11,868	182 ms
26	Braze	4,646	183 ms
27	DotMetrics	1,095	190 ms
28	Searchanise	2,106	199 ms
29	Google Analytics	7,354,488	204 ms
30	Mixpanel	23,834	208 ms
31	CleverTap	1,411	211 ms
32	Amplitude Mobile Analytics	20,663	211 ms
33	Marchex	12,237	230 ms
34	Snowplow	52,580	231 ms
35	Marketo	4,936	233 ms
36	Qualtrics	8,261	261 ms
37	Google Optimize	109,605	283 ms
38	Chartbeat	8,441	298 ms
39	Smart Insight Tracking	2,364	301 ms
40	Matomo	7,783	304 ms
41	Kameleoon	2,080	314 ms
42	CallRail	30,191	319 ms
43	Radar	1,205	326 ms
44	Reviews.co.uk	2,343	335 ms
45	Trust Pilot	46,920	338 ms
46	etracker	5,735	343 ms
47	Heap	17,746	351 ms
48	Usabilla	4,917	377 ms
49	Reviews.io	3,203	380 ms
50	Evergage	3,244	436 ms
51	Nielsen NetRatings SiteCensus	30,311	442 ms
52	mPulse	30,704	448 ms
53	Snapchat	53,440	451 ms
54	Crazy Egg	54,354	477 ms
55	Exponea	1,300	480 ms
56	Baidu Analytics	41,199	484 ms
57	Pendo	13,739	493 ms
58	Parse.ly	10,444	523 ms
59	Net Reviews	4,403	540 ms
60	Segment	34,916	556 ms
61	PageSense	4,861	610 ms
62	Convert Insights	1,326	646 ms
63	BowNow	2,480	651 ms
64	Bazaarvoice	3,306	691 ms
65	VWO	9,654	718 ms
66	Optimizely	38,211	745 ms
67	Evidon	3,955	805 ms
68	FullStory	19,055	816 ms
69	Feefo.com	2,467	838 ms
70	Nosto	1,475	889 ms
71	Clerk.io ApS	2,191	918 ms
72	PowerReviews	1,712	988 ms
73	Kampyle	1,182	1013 ms
74	AB Tasty	2,349	1036 ms
75	ContentSquare	2,921	1049 ms
76	Revolver Maps	4,529	1057 ms
77	Mouseflow	9,147	1086 ms
78	Hotjar	388,625	1128 ms
79	Lucky Orange	22,963	1171 ms
80	Survicate	4,316	1215 ms
81	Histats	40,738	1271 ms
82	TrackJS	2,872	1313 ms
83	Quantum Metric	1,370	1391 ms
84	Dynatrace	1,297	1397 ms
85	Salesforce	2,633	1447 ms
86	Yandex Metrica	678,046	1779 ms
87	Gigya	2,704	1899 ms
88	Inspectlet	7,027	1923 ms
89	Ezoic	3,721	4215 ms

Social

These scripts enable social features.

Rank	Name	Usage	Average Impact
1	reddit	10,118	91 ms
2	Shareaholic	9,329	111 ms
3	AddToAny	136,021	130 ms
4	Pinterest	242,284	197 ms
5	Spot.IM	4,196	213 ms
6	LinkedIn	26,875	380 ms
7	Facebook	3,615,665	538 ms
8	AddShoppers	2,511	572 ms
9	Kakao	76,443	628 ms
10	ShareThis	145,513	747 ms
11	TikTok	183,382	1005 ms
12	AddThis	170,871	1697 ms
13	SocialShopWave	4,778	1882 ms
14	Instagram	14,742	2092 ms
15	VK	83,670	2266 ms
16	Disqus	1,751	2951 ms
17	PIXNET	22,999	3641 ms
18	Twitter	474,202	4262 ms
19	Tumblr	31,246	5477 ms
20	LiveJournal	12,919	6195 ms

Video

These scripts enable video player and streaming functionality.

Rank	Name	Usage	Average Impact
1	AdMan Media	1,264	10 ms
2	Brightcove	25,103	1565 ms
3	Vimeo	155,149	3223 ms
4	Wistia	32,761	4198 ms
5	Twitch	1,700	5029 ms
6	YouTube	1,300,884	5670 ms

Developer Utilities

These scripts are developer utilities (API clients, site monitoring, fraud detection, etc).

Rank	Name	Usage	Average Impact
1	Rollbar	5,014	64 ms
2	Webmarked	1,259	74 ms
3	Checkout.com	1,047	80 ms
4	PrintFriendly	1,203	83 ms
5	Raygun	4,080	89 ms
6	CyberSource (Visa)	2,271	96 ms
7	AddEvent	1,948	101 ms
8	Pusher	2,077	103 ms
9	Siteimprove	14,471	108 ms
10	Cloudflare	261,995	152 ms
11	Braintree Payments	1,136	166 ms
12	iovation	2,419	176 ms
13	Accessibe Accessibility Overlay	43,816	185 ms
14	Key CDN	7,552	186 ms
15	Ipify	2,710	192 ms
16	Bitly	3,065	205 ms
17	Seznam	12,956	221 ms
18	Highcharts	3,309	227 ms
19	New Relic	275,206	264 ms
20	GitHub	10,929	282 ms
21	Netlify	1,342	285 ms
22	Riskified	1,989	319 ms
23	LightWidget	13,037	331 ms
24	Other Google APIs/SDKs	3,654,894	334 ms
25	Amazon Pay	6,494	348 ms
26	Foxentry	2,025	349 ms
27	Sift Science	1,630	351 ms
28	Klevu Search	1,813	427 ms
29	Clarity	199,675	430 ms
30	OneSignal	79,504	436 ms
31	Cookie-Script.com	18,827	440 ms
32	iubenda	88,539	446 ms
33	Swiftype	1,427	451 ms
34	Bold Commerce	17,769	454 ms
35	TrustArc	6,724	486 ms
36	Affirm	6,758	537 ms
37	Trusted Shops	18,598	538 ms
38	Hexton	40,690	556 ms
39	ThreatMetrix	3,878	556 ms
40	Google reCAPTCHA	28,814	565 ms
41	Wufoo	2,770	572 ms
42	Bugsnag	11,619	633 ms
43	GetSiteControl	3,601	694 ms
44	Sentry	63,554	735 ms
45	Yandex APIs	55,547	771 ms
46	WisePops	3,280	857 ms
47	Forter	5,093	950 ms
48	Auth0	1,884	970 ms
49	Google Maps	1,408,194	975 ms
50	Mapbox	19,625	991 ms
51	Vidyard	1,729	1057 ms
52	AppDynamics	4,187	1059 ms
53	GoDaddy	108,110	1228 ms
54	Cookiebot	125,568	1292 ms
55	Secomapp	3,976	1339 ms
56	PayPal	69,556	1348 ms
57	Signyfyd	1,857	1524 ms
58	Luigis Box	1,789	1564 ms
59	Stripe	116,149	1631 ms
60	Adyen	2,073	2491 ms
61	Fastly	9,510	2703 ms
62	POWr	44,682	5336 ms
63	Esri ArcGIS	4,071	5653 ms
64	Rambler	23,957	5680 ms

Hosting Platforms

These scripts are from web hosting platforms (WordPress, Wix, Squarespace, etc). Note that in this category, this can sometimes be the entirety of script on the page, and so the "impact" rank might be misleading. In the case of WordPress, this just indicates the libraries hosted and served by WordPress not all sites using self-hosted WordPress.

Rank	Name	Usage	Average Impact
1	Blogger	353,571	157 ms
2	Civic	6,235	426 ms
3	Typepad	1,593	621 ms
4	Dealer	2,026	673 ms
5	WordPress	439,506	793 ms
6	Yottaa	1,062	967 ms
7	Rackspace	2,809	1117 ms
8	Ecwid	6,754	1260 ms
9	Tilda	69,491	1572 ms
10	Salesforce Commerce Cloud	4,302	1627 ms
11	Shopify	473,611	3232 ms
12	Hatena Blog	50,895	3966 ms
13	Squarespace	225,045	4250 ms
14	Webflow	54,914	4705 ms
15	WebsiteBuilder.com	5,957	4748 ms
16	Wix	416,155	4939 ms
17	Weebly	77,216	5310 ms

Marketing

These scripts are from marketing tools that add popups/newsletters/etc.

Rank	Name	Usage	Average Impact
1	Zync	1,396	16 ms
2	Kargo	20,376	25 ms
3	NEORY Marketing Cloud	1,179	50 ms
4	SalesLoft	2,008	64 ms
5	Madison Logic	12,270	79 ms
6	Podsights	2,333	83 ms
7	Albacross	2,706	83 ms
8	Pardot	4,158	113 ms
9	DemandBase	3,172	124 ms
10	SATORI	1,098	156 ms
11	Wicked Reports	2,578	218 ms
12	Convertful	2,195	234 ms
13	Sojern	4,598	367 ms
14	RD Station	24,872	428 ms
15	Listrak	1,310	590 ms
16	Mailchimp	61,368	648 ms
17	OptinMonster	4,166	667 ms
18	Yotpo	28,110	751 ms
19	Hubspot	152,331	795 ms
20	Wishpond Technologies	1,808	796 ms
21	iZooto	2,033	969 ms
22	Judge.me	36,631	1112 ms
23	Beeketing	3,590	1565 ms
24	Wunderkind	1,937	1596 ms
25	KARTE	1,716	1615 ms
26	PureCars	2,464	1788 ms
27	Sumo	17,982	2007 ms
28	Bigcommerce	22,100	2828 ms
29	Drift	9,192	5219 ms
30	Tray Commerce	12,754	5250 ms

Customer Success

These scripts are from customer support/marketing providers that offer chat and contact solutions. These scripts are generally heavier in weight.

Rank	Name	Usage	Average Impact
1	Provide Support	1,591	86 ms
2	Crisp	1,894	116 ms
3	Salesforce Live Agent	1,339	133 ms
4	SnapEngage	1,578	162 ms
5	ClickDesk	1,178	211 ms
6	LiveTex	2,570	240 ms
7	BoldChat	1,580	254 ms
8	Foursixty	1,974	266 ms
9	Pure Chat	5,132	421 ms
10	Help Scout	5,156	474 ms
11	WebEngage	1,770	525 ms
12	iPerceptions	5,705	687 ms
13	Comm100	1,151	853 ms
14	Jivochat	82,226	1024 ms
15	LivePerson	4,611	1041 ms
16	Smartsupp	28,543	1215 ms
17	Intercom	32,604	1253 ms
18	Tawk.to	133,508	1331 ms
19	LiveChat	48,233	1503 ms
20	Tidio Live Chat	35,664	1550 ms
21	Olark	9,005	1962 ms
22	ZenDesk	96,167	2052 ms
23	Dynamic Yield	2,369	2715 ms
24	Freshchat	8,774	3931 ms

Content & Publishing

These scripts are from content providers or publishing-specific affiliate tracking.

Rank	Name	Usage	Average Impact
1	Spotify	12,053	9 ms
2	TripAdvisor	5,806	156 ms
3	Accuweather	2,150	227 ms
4	Tencent	13,956	254 ms
5	SnapWidget	17,318	257 ms
6	Flowplayer	1,184	284 ms
7	CPEx	2,623	325 ms
8	OpenTable	4,694	546 ms
9	Booking.com	3,517	555 ms
10	Cloudinary	2,883	569 ms
11	Revcontent	1,487	1039 ms
12	Covert Pics	3,269	1460 ms
13	AMP	48,306	1479 ms
14	Embedly	11,957	1499 ms
15	Kaltura Video Platform	1,159	2196 ms
16	issuu	3,420	2398 ms
17	Hotmart	6,593	2841 ms
18	SoundCloud	8,176	2842 ms
19	Dailymotion	4,861	7911 ms
20	Medium	14,238	11534 ms

CDNs

These are a mixture of publicly hosted open source libraries (e.g. jQuery) served over different public CDNs and private CDN usage. This category is unique in that the origin may have no responsibility for the performance of what's being served. Note that rank here does not imply one CDN is better than the other. It simply indicates that the scripts being served from that origin are lighter/heavier than the ones served by another.

Rank	Name	Usage	Average Impact
1	Cloud.typography	1,856	0 ms
2	Google Fonts	401,345	0 ms
3	Bootstrap CDN	100,484	46 ms
4	FontAwesome CDN	365,810	204 ms
5	Adobe TypeKit	185,891	267 ms
6	Monotype	5,700	288 ms
7	jQuery CDN	753,144	475 ms
8	Akamai	16,257	505 ms
9	JSDelivr CDN	453,827	515 ms
10	Cloudflare CDN	687,571	528 ms
11	Fort Awesome	2,939	591 ms
12	Bootstrap Chinese network	1,204	604 ms
13	Azure Web Services	55,970	647 ms
14	Unpkg	138,570	893 ms
15	Google CDN	3,514,217	1163 ms
16	Yandex CDN	207,860	1950 ms
17	Microsoft Hosted Libs	33,934	2340 ms
18	CreateJS CDN	5,426	4148 ms

Tag Management

These scripts tend to load lots of other scripts and initiate many tasks.

Rank	Name	Usage	Average Impact
1	BrightTag / Signal	5,238	290 ms
2	Adobe Tag Manager	231,853	306 ms
3	Yahoo! Tag Manager	13,368	346 ms
4	TagCommander	1,922	424 ms
5	Google Tag Manager	7,142,617	584 ms
6	Ensighten	5,173	838 ms
7	Tealium	29,596	971 ms

Consent Management Provider

IAB Consent Management Providers are the 'Cookie Consent' popups used by many publishers. They're invoked for every page and sit on the critical path between a page loading and adverts being displayed.

Rank	Name	Usage	Average Impact
1	Trustcommander	3,172	210 ms
2	Quantcast Choice	28,649	406 ms
3	Optanon	114,546	615 ms
4	Consent Manager CMP	3,749	980 ms
5	Usercentrics CMP	49,319	1965 ms

Mixed / Other

These are miscellaneous scripts delivered via a shared origin with no precise category or attribution. Help us out by identifying more origins!

Rank	Name	Usage	Average Impact
1	Browser-Update.org	2,899	76 ms
2	ReadSpeaker	6,735	119 ms
3	ResponsiveVoice	6,490	153 ms
4	Arbor	1,180	177 ms
5	Skype	2,262	215 ms
6	Polyfill service	2,098	253 ms
7	Browsealoud	2,437	506 ms
8	Sirv	1,060	537 ms
9	Amazon Web Services	133,777	616 ms
10	Calendly	7,789	1388 ms
11	Heroku	21,607	1759 ms
12	uLogin	1,807	3188 ms

Third Parties by Total Impact

This section highlights the entities responsible for the most script execution across the web. This helps inform which improvements would have the largest total impact.

Name	Popularity	Total Impact	Average Impact
YouTube	1,300,884	7,375,711 s	5670 ms
Google Tag Manager	7,142,617	4,168,635 s	584 ms
Google/Doubleclick Ads	1,696,595	4,100,765 s	2417 ms
Google CDN	3,514,217	4,087,129 s	1163 ms
Wix	416,155	2,055,559 s	4939 ms
Twitter	474,202	2,021,092 s	4262 ms
Facebook	3,615,665	1,944,373 s	538 ms
Shopify	473,611	1,530,614 s	3232 ms
Google Analytics	7,354,488	1,501,819 s	204 ms
Google Maps	1,408,194	1,372,305 s	975 ms
Other Google APIs/SDKs	3,654,894	1,221,839 s	334 ms
Yandex Metrica	678,046	1,206,168 s	1779 ms
Squarespace	225,045	956,369 s	4250 ms
Pubmatic	309,062	504,653 s	1633 ms
Vimeo	155,149	500,039 s	3223 ms
Hotjar	388,625	438,255 s	1128 ms
Weebly	77,216	410,032 s	5310 ms
Yandex CDN	207,860	405,383 s	1950 ms
Cloudflare CDN	687,571	363,267 s	528 ms
jQuery CDN	753,144	357,816 s	475 ms
WordPress	439,506	348,683 s	793 ms
AddThis	170,871	289,947 s	1697 ms
Webflow	54,914	258,374 s	4705 ms
POWr	44,682	238,406 s	5336 ms
JSDelivr CDN	453,827	233,595 s	515 ms
Hatena Blog	50,895	201,838 s	3966 ms
ZenDesk	96,167	197,305 s	2052 ms
VK	83,670	189,624 s	2266 ms
Stripe	116,149	189,426 s	1631 ms
WordAds	105,042	188,281 s	1792 ms
TikTok	183,382	184,325 s	1005 ms
Tawk.to	133,508	177,651 s	1331 ms
Tumblr	31,246	171,137 s	5477 ms
Medium	14,238	164,218 s	11534 ms
Cookiebot	125,568	162,245 s	1292 ms
Media.net	126,029	162,062 s	1286 ms
Wistia	32,761	137,540 s	4198 ms
Rambler	23,957	136,083 s	5680 ms
GoDaddy	108,110	132,733 s	1228 ms
Rubicon Project	278,207	131,103 s	471 ms
Unpkg	138,570	123,718 s	893 ms
Hubspot	152,331	121,088 s	795 ms
Tilda	69,491	109,220 s	1572 ms
ShareThis	145,513	108,626 s	747 ms
Bridgewell DSP	22,900	99,126 s	4329 ms
Usercentrics CMP	49,319	96,920 s	1965 ms
PayPal	69,556	93,743 s	1348 ms
Clarity	199,675	85,917 s	430 ms
Jivochat	82,226	84,189 s	1024 ms
PIXNET	22,999	83,729 s	3641 ms
Klaviyo	123,185	82,397 s	669 ms
Amazon Web Services	133,777	82,341 s	616 ms
Criteo	253,709	81,982 s	323 ms
LiveJournal	12,919	80,027 s	6195 ms
Microsoft Hosted Libs	33,934	79,421 s	2340 ms
FontAwesome CDN	365,810	74,512 s	204 ms
New Relic	275,206	72,635 s	264 ms
LiveChat	48,233	72,477 s	1503 ms
AMP	48,306	71,469 s	1479 ms
Adobe Tag Manager	231,853	71,024 s	306 ms
Optanon	114,546	70,445 s	615 ms
Tray Commerce	12,754	66,954 s	5250 ms
Bigcommerce	22,100	62,488 s	2828 ms
Tynt	172,762	56,038 s	324 ms
Blogger	353,571	55,578 s	157 ms
Tidio Live Chat	35,664	55,288 s	1550 ms
Histats	40,738	51,763 s	1271 ms
Amazon Ads	295,346	51,175 s	173 ms
Connatix	12,943	49,929 s	3858 ms
Adobe TypeKit	185,891	49,693 s	267 ms
Yahoo! JAPAN Ads	78,117	49,129 s	629 ms
Kakao	76,443	47,988 s	628 ms
Drift	9,192	47,972 s	5219 ms
Pinterest	242,284	47,729 s	197 ms
Sentry	63,554	46,700 s	735 ms
Skimbit	95,914	43,466 s	453 ms
Yandex APIs	55,547	42,848 s	771 ms
Intercom	32,604	40,849 s	1253 ms
Judge.me	36,631	40,738 s	1112 ms
Mediavine	9,994	40,591 s	4061 ms
Cloudflare	261,995	39,758 s	152 ms
Mailchimp	61,368	39,753 s	648 ms
iubenda	88,539	39,517 s	446 ms
Brightcove	25,103	39,283 s	1565 ms
Crowd Control	91,065	38,503 s	423 ms
Dailymotion	4,861	38,453 s	7911 ms
Heroku	21,607	38,015 s	1759 ms
Taboola	47,105	37,765 s	802 ms
Infolinks	55,394	36,720 s	663 ms
Azure Web Services	55,970	36,198 s	647 ms
Sumo	17,982	36,096 s	2007 ms
Smartsupp	28,543	34,687 s	1215 ms
OneSignal	79,504	34,638 s	436 ms
Freshchat	8,774	34,489 s	3931 ms
Google Optimize	109,605	31,072 s	283 ms
Technorati	89,172	30,946 s	347 ms
Instagram	14,742	30,844 s	2092 ms
Tealium	29,596	28,723 s	971 ms
Optimizely	38,211	28,484 s	745 ms
WebsiteBuilder.com	5,957	28,286 s	4748 ms
Lucky Orange	22,963	26,896 s	1171 ms
Crazy Egg	54,354	25,900 s	477 ms
Fastly	9,510	25,704 s	2703 ms
MGID	10,762	24,314 s	2259 ms
Snapchat	53,440	24,100 s	451 ms
SoundCloud	8,176	23,239 s	2842 ms
Esri ArcGIS	4,071	23,015 s	5653 ms
Hexton	40,690	22,608 s	556 ms
CreateJS CDN	5,426	22,505 s	4148 ms
Yotpo	28,110	21,099 s	751 ms
VigLink	50,677	20,430 s	403 ms
Baidu Analytics	41,199	19,939 s	484 ms
BlueKai	99,102	19,881 s	201 ms
Quantcast	135,222	19,832 s	147 ms
Yahoo! Ad Exchange	4,809	19,685 s	4093 ms
Mapbox	19,625	19,440 s	991 ms
Segment	34,916	19,426 s	556 ms
Hotmart	6,593	18,730 s	2841 ms
Integral Ad Science	25,510	18,494 s	725 ms
Embedly	11,957	17,922 s	1499 ms
AddToAny	136,021	17,691 s	130 ms
Olark	9,005	17,669 s	1962 ms
Privy	24,457	17,566 s	718 ms
Smart AdServer	69,072	17,356 s	251 ms
LinkedIn Ads	189,262	16,869 s	89 ms
WordPress Site Stats	250,050	16,686 s	67 ms
Sizmek	6,979	16,542 s	2370 ms
Google reCAPTCHA	28,814	16,280 s	565 ms
Trust Pilot	46,920	15,841 s	338 ms
Ezoic	3,721	15,684 s	4215 ms
FullStory	19,055	15,558 s	816 ms
Index Exchange	193,085	15,200 s	79 ms
Bing Ads	60,072	13,800 s	230 ms
Adroll	35,751	13,757 s	385 ms
mPulse	30,704	13,757 s	448 ms
Inspectlet	7,027	13,509 s	1923 ms
AudienceSearch	63,098	13,507 s	214 ms
Nielsen NetRatings SiteCensus	30,311	13,393 s	442 ms
GumGum	147,038	12,868 s	88 ms
IPONWEB	33,059	12,451 s	377 ms
Snowplow	52,580	12,120 s	231 ms
Twitter Online Conversion Tracking	107,645	12,007 s	112 ms
Quantcast Choice	28,649	11,633 s	406 ms
Attentive	9,725	11,108 s	1142 ms
OptiMonk	10,355	11,003 s	1063 ms
Yandex Ads	17,572	11,001 s	626 ms
Moat	15,290	10,934 s	715 ms
Calendly	7,789	10,814 s	1388 ms
AppNexus	192,000	10,783 s	56 ms
Supership	20,178	10,717 s	531 ms
RD Station	24,872	10,644 s	428 ms
DTSCOUT	52,864	10,519 s	199 ms
LinkedIn	26,875	10,221 s	380 ms
Outbrain	66,714	10,056 s	151 ms
Trusted Shops	18,598	10,013 s	538 ms
Mouseflow	9,147	9,936 s	1086 ms
CallRail	30,191	9,623 s	319 ms
sovrn	74,072	9,006 s	122 ms
SocialShopWave	4,778	8,993 s	1882 ms
Geniee	23,506	8,905 s	379 ms
TrafficStars	12,308	8,590 s	698 ms
Twitch	1,700	8,549 s	5029 ms
Ecwid	6,754	8,510 s	1260 ms
Cookie-Script.com	18,827	8,286 s	440 ms
LongTail Ad Solutions	8,471	8,262 s	975 ms
ID5 Identity Cloud	78,299	8,235 s	105 ms
Akamai	16,257	8,210 s	505 ms
issuu	3,420	8,201 s	2398 ms
StatCounter	62,405	8,181 s	131 ms
Accessibe Accessibility Overlay	43,816	8,115 s	185 ms
fluct	27,604	8,108 s	294 ms
Bold Commerce	17,769	8,074 s	454 ms
Bugsnag	11,619	7,355 s	633 ms
Conversant	56,953	7,070 s	124 ms
Salesforce Commerce Cloud	4,302	6,998 s	1627 ms
VWO	9,654	6,931 s	718 ms
Pendo	13,739	6,767 s	493 ms
Seedtag	3,321	6,630 s	1996 ms
Gemius	34,117	6,616 s	194 ms
Afterpay	21,232	6,549 s	308 ms
Dynamic Yield	2,369	6,431 s	2715 ms
Heap	17,746	6,230 s	351 ms
Cxense	5,410	6,149 s	1137 ms
LINE Corporation	30,410	6,140 s	202 ms
i-mobile	15,890	5,846 s	368 ms
uLogin	1,807	5,760 s	3188 ms
Beeketing	3,590	5,619 s	1565 ms
Parse.ly	10,444	5,464 s	523 ms
Secomapp	3,976	5,323 s	1339 ms
Survicate	4,316	5,245 s	1215 ms
Disqus	1,751	5,168 s	2951 ms
Adyen	2,073	5,163 s	2491 ms
Gigya	2,704	5,135 s	1899 ms
LoyaltyLion	4,962	5,098 s	1027 ms
Mixpanel	23,834	4,959 s	208 ms
Forter	5,093	4,840 s	950 ms
LivePerson	4,611	4,801 s	1041 ms
DoubleVerify	2,657	4,796 s	1805 ms
Revolver Maps	4,529	4,785 s	1057 ms
Covert Pics	3,269	4,774 s	1460 ms

Future Work

1. Introduce URL-level data for more fine-grained analysis, i.e. which libraries from Cloudflare/Google CDNs are most expensive.
2. Expand the scope, i.e. include more third parties and have greater entity/category coverage.

FAQs

I don't see entity X in the list. What's up with that?

This can be for one of several reasons:

1. The entity does not have references to their origin on at least 50 pages in the dataset.
2. The entity's origins have not yet been identified. See How can I contribute?

What is "Total Occurences"?

Total Occurrences is the number of pages on which the entity is included.

How is the "Average Impact" determined?

The HTTP Archive dataset includes Lighthouse reports for each URL on mobile. Lighthouse has an audit called "bootup-time" that summarizes the amount of time that each script spent on the main thread. The "Average Impact" for an entity is the total execution time of scripts whose domain matches one of the entity's domains divided by the total number of pages that included the entity.

Average Impact = Total Execution Time / Total Occurrences

How does Lighthouse determine the execution time of each script?

Lighthouse's bootup time audit attempts to attribute all toplevel main-thread tasks to a URL. A main thread task is attributed to the first script URL found in the stack. If you're interested in helping us improve this logic, see Contributing for details.

The data for entity X seems wrong. How can it be corrected?

Verify that the origins in data/entities.js are correct. Most issues will simply be the result of mislabelling of shared origins. If everything checks out, there is likely no further action and the data is valid. If you still believe there's errors, file an issue to discuss futher.

How can I contribute?

Only about 90% of the third party script execution has been assigned to an entity. We could use your help identifying the rest! See Contributing for details.

Contributing

Thanks

A huge thanks to @simonhearne and @soulgalore for their assistance in classifying additional domains!

Updating the Entities

The domain->entity mapping can be found in data/entities.js. Adding a new entity is as simple as adding a new array item with the following form.

{
    "name": "Facebook",
    "homepage": "https://www.facebook.com",
    "category": "social",
    "domains": [
        "*.facebook.com",
        "*.fbcdn.net"
    ],
    "examples": [
        "www.facebook.com",
        "connect.facebook.net",
        "staticxx.facebook.com",
        "static.xx.fbcdn.net",
        "m.facebook.com"
    ]
}

Updating Attribution Logic

The logic for attribution to individual script URLs can be found in the Lighthouse repo. File an issue over there to discuss further.

Updating the Data

This is now automated! Run yarn start:update-ha-data with a gcp-credentials.json file in the root directory of this project (look at bin/automated-update.js for the steps involved).

Updating this README

This README is auto-generated from the templates lib/ and the computed data. In order to update the charts, you'll need to make sure you have cairo installed locally in addition to yarn install.

# Install `cairo` and dependencies for node-canvas
brew install pkg-config cairo pango libpng jpeg giflib
# Build the requirements in this repo
yarn build
# Regenerate the README
yarn start

Updating the website

The web code is located in www/ directory of this repository. Open a PR to make changes.