third-party-web

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	Truffle Bid	17,556	0 ms
2	Bidswitch	39,349	0 ms
3	Unruly Media	6,983	0 ms
4	Nativo	28,406	0 ms
5	AcuityAds	9,415	0 ms
6	AdGear	48,485	1 ms
7	Tribal Fusion	121,668	1 ms
8	MaxPoint Interactive	12,319	1 ms
9	Beeswax	10,108	1 ms
10	Crimtan	57,806	1 ms
11	TripleLift	3,251	1 ms
12	adKernel	12,242	1 ms
13	iPROM	55,739	2 ms
14	Bidtellect	10,797	2 ms
15	InMobi	66,361	2 ms
16	OpenX	11,228	12 ms
17	33 Across	143,025	17 ms
18	Adform	86,041	21 ms
19	AppNexus	177,948	22 ms
20	GumGum	123,913	25 ms
21	LoopMe	42,797	33 ms
22	Constant Contact	17,757	34 ms
23	Adyoulike	4,229	40 ms
24	Sonobi	54,964	50 ms
25	sovrn	19,694	59 ms
26	OneTag	29,755	60 ms
27	RTB House AdPilot	5,708	61 ms
28	Simpli.fi	10,407	63 ms
29	MailMunch	17,494	66 ms
30	The Trade Desk	15,933	69 ms
31	BlueCava	5,973	77 ms
32	Twitter Online Conversion Tracking	68,128	79 ms
33	DTSCOUT	5,825	81 ms
34	ActiveCampaign	14,775	83 ms
35	StackAdapt	13,484	84 ms
36	Scorecard Research	46,696	87 ms
37	Branch Metrics	13,768	90 ms
38	Affiliate Window	4,621	93 ms
39	Quora Ads	9,098	103 ms
40	LinkedIn Ads	187,285	104 ms
41	Criteo	165,842	118 ms
42	Index Exchange	33,560	118 ms
43	Impact Radius	4,158	127 ms
44	Rakuten Marketing	3,189	127 ms
45	Microad	12,512	129 ms
46	LINE Corporation	24,991	138 ms
47	Crowd Control	70,113	138 ms
48	Bing Ads	45,421	146 ms
49	Gemius	15,825	149 ms
50	AudienceSearch	51,541	156 ms
51	Intercept Interactive	18,824	160 ms
52	ucfunnel ucX	8,896	163 ms
53	IPONWEB	19,682	164 ms
54	Simplicity Marketing	2,983	166 ms
55	AdRiver	4,609	170 ms
56	STINGRAY	7,281	171 ms
57	Salesforce.com	4,381	185 ms
58	Yahoo!	8,039	190 ms
59	Technorati	22,378	193 ms
60	i-mobile	11,882	195 ms
61	Unbounce	9,100	199 ms
62	Tynt	162,031	207 ms
63	Outbrain	11,439	210 ms
64	Smart AdServer	109,986	213 ms
65	ID5 Identity Cloud	65,666	241 ms
66	Media.net	93,229	244 ms
67	TrafficStars	7,539	275 ms
68	Amazon Ads	178,313	288 ms
69	Adroll	31,186	321 ms
70	Skimbit	81,338	326 ms
71	Teads	6,909	331 ms
72	LiveRamp Privacy Manager	18,855	339 ms
73	fluct	22,281	341 ms
74	Supership	18,113	379 ms
75	Yandex Ads	8,817	460 ms
76	Attentive	9,166	514 ms
77	Cxense	3,731	533 ms
78	Yahoo! JAPAN Ads	53,919	564 ms
79	OptiMonk	10,492	607 ms
80	VigLink	6,674	621 ms
81	Klaviyo	142,926	628 ms
82	Privy	19,432	633 ms
83	WordAds	102,326	654 ms
84	Geniee	14,510	681 ms
85	Taboola	50,480	714 ms
86	AdScore	4,378	771 ms
87	LongTail Ad Solutions	6,143	776 ms
88	LoyaltyLion	4,213	815 ms
89	Integral Ad Science	15,169	827 ms
90	Rubicon Project	220,488	994 ms
91	Moat	3,861	1039 ms
92	DoubleVerify	4,740	1171 ms
93	Seedtag	2,513	1505 ms
94	Sizmek	5,738	1579 ms
95	Pubmatic	221,339	1673 ms
96	Infolinks	5,954	1749 ms
97	MGID	9,908	1916 ms
98	Google/Doubleclick Ads	1,172,494	2968 ms
99	Yahoo! Ad Exchange	4,858	2974 ms
100	Mediavine	9,730	4101 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	Mouseflow	4,985	48 ms
2	SpeedCurve RUM	2,169	53 ms
3	WordPress Site Stats	64,925	56 ms
4	Roxr Software	11,383	63 ms
5	Pingdom RUM	1,008	65 ms
6	Movable Ink	3,989	80 ms
7	Sailthru	1,394	84 ms
8	LiveRamp IdentityLink	1,878	88 ms
9	Woopra	1,274	89 ms
10	Treasure Data	13,593	95 ms
11	mPulse	32,660	98 ms
12	Smartlook	17,274	101 ms
13	XiTi	4,514	103 ms
14	StatCounter	51,587	104 ms
15	Fastly Insights	1,631	108 ms
16	Exponea	1,330	111 ms
17	Conversant	46,153	112 ms
18	Google Analytics	4,492,386	113 ms
19	Brandmetrics	14,878	115 ms
20	Okta	3,161	118 ms
21	CleverTap	1,211	127 ms
22	Polldaddy	2,255	128 ms
23	Stamped.io	12,632	134 ms
24	Snowplow	59,526	139 ms
25	Google Optimize	41,792	154 ms
26	Marchex	8,398	160 ms
27	Usabilla	1,272	161 ms
28	Braze	1,801	161 ms
29	Mixpanel	20,441	163 ms
30	Quantcast	68,514	164 ms
31	Reviews.co.uk	1,896	169 ms
32	Qualtrics	5,917	172 ms
33	Smart Insight Tracking	1,731	193 ms
34	Matomo	12,297	195 ms
35	Amplitude Mobile Analytics	36,223	195 ms
36	Chartbeat	6,715	205 ms
37	Parse.ly	6,157	223 ms
38	Baidu Analytics	33,318	227 ms
39	Trust Pilot	44,933	240 ms
40	CallRail	28,866	247 ms
41	UpSellit	1,994	249 ms
42	etracker	5,608	270 ms
43	Marketo	1,126	283 ms
44	PageSense	5,617	297 ms
45	Nielsen NetRatings SiteCensus	17,440	345 ms
46	Survicate	3,308	353 ms
47	Pendo	13,333	357 ms
48	Segment	27,196	370 ms
49	Reviews.io	4,148	375 ms
50	Heap	13,234	377 ms
51	Evergage	2,658	387 ms
52	Snapchat	49,940	393 ms
53	Bazaarvoice	3,262	432 ms
54	Net Reviews	2,784	445 ms
55	Crazy Egg	20,553	485 ms
56	AB Tasty	3,343	492 ms
57	BowNow	2,295	495 ms
58	Evidon	2,382	496 ms
59	Convert Insights	4,173	522 ms
60	Nosto	1,173	607 ms
61	Feefo.com	2,034	619 ms
62	VWO	8,018	639 ms
63	Hotjar	331,044	661 ms
64	TrackJS	2,353	718 ms
65	FullStory	13,438	724 ms
66	Clerk.io ApS	1,910	776 ms
67	PowerReviews	1,524	804 ms
68	Lucky Orange	14,012	831 ms
69	Optimizely	15,596	857 ms
70	ContentSquare	3,541	912 ms
71	Revolver Maps	2,172	972 ms
72	Dynatrace	3,420	1121 ms
73	Gigya	2,032	1243 ms
74	Quantum Metric	1,170	1266 ms
75	Inspectlet	5,338	1469 ms
76	Yandex Metrica	596,366	1899 ms

Social

These scripts enable social features.

Rank	Name	Usage	Average Impact
1	Shareaholic	1,294	86 ms
2	Pinterest	131,399	144 ms
3	AddToAny	66,597	146 ms
4	reddit	16,277	238 ms
5	LinkedIn	17,125	306 ms
6	ShareThis	88,925	338 ms
7	AddShoppers	1,915	340 ms
8	Facebook	3,181,086	388 ms
9	TikTok	215,993	457 ms
10	Kakao	63,733	642 ms
11	PIXNET	15,360	709 ms
12	Instagram	10,222	1260 ms
13	SocialShopWave	4,310	1501 ms
14	Twitter	331,511	2185 ms
15	VK	24,107	2366 ms
16	Disqus	1,135	2724 ms
17	Tumblr	17,786	2804 ms
18	LiveJournal	9,526	5835 ms

Video

These scripts enable video player and streaming functionality.

Rank	Name	Usage	Average Impact
1	Brightcove	13,124	1092 ms
2	Vimeo	141,109	2848 ms
3	Wistia	26,714	3186 ms
4	Twitch	1,450	4518 ms
5	YouTube	962,443	4991 ms

Developer Utilities

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

Rank	Name	Usage	Average Impact
1	Checkout.com	1,117	61 ms
2	Siteimprove	9,172	76 ms
3	Raygun	2,110	89 ms
4	Rollbar	1,442	93 ms
5	Pusher	1,456	94 ms
6	iovation	2,098	108 ms
7	CyberSource (Visa)	2,061	118 ms
8	Afterpay	7,898	124 ms
9	Cloudflare	348,270	125 ms
10	Ipify	2,159	132 ms
11	Braintree Payments	1,010	136 ms
12	Macropod BugHerd	2,677	138 ms
13	Wufoo	1,556	148 ms
14	Seznam	9,260	158 ms
15	Bitly	2,973	158 ms
16	Amazon Pay	6,678	161 ms
17	Key CDN	5,597	186 ms
18	Netlify	1,323	194 ms
19	Highcharts	3,106	214 ms
20	Riskified	1,848	218 ms
21	LightWidget	11,137	226 ms
22	Cookie-Script.com	41,414	227 ms
23	OneSignal	66,991	254 ms
24	New Relic	234,387	261 ms
25	Foxentry	1,927	270 ms
26	TrustArc	7,377	294 ms
27	Google reCAPTCHA	27,115	304 ms
28	Cookiebot	171,303	308 ms
29	Accessibe Accessibility Overlay	48,040	313 ms
30	Swiftype	1,096	350 ms
31	Hexton	32,051	352 ms
32	iubenda	93,812	356 ms
33	Clarity	338,320	359 ms
34	Trusted Shops	17,034	369 ms
35	Other Google APIs/SDKs	2,358,410	378 ms
36	Bugsnag	13,395	397 ms
37	GitHub	6,970	434 ms
38	Bold Commerce	11,923	435 ms
39	Klevu Search	1,415	437 ms
40	GetSiteControl	3,062	476 ms
41	Affirm	6,594	500 ms
42	Sentry	89,800	577 ms
43	ThreatMetrix	2,935	606 ms
44	Yandex APIs	44,655	621 ms
45	Google Maps	1,214,682	633 ms
46	Mapbox	19,297	663 ms
47	PayPal	56,797	879 ms
48	AppDynamics	3,419	907 ms
49	GoDaddy	122,066	938 ms
50	Forter	4,345	943 ms
51	Vidyard	1,061	978 ms
52	Secomapp	2,220	1102 ms
53	Stripe	127,044	1133 ms
54	Luigis Box	2,210	1217 ms
55	Marker	1,508	1238 ms
56	WisePops	2,044	1241 ms
57	Signyfyd	2,567	1495 ms
58	Fastly	9,099	1679 ms
59	Adyen	2,322	2052 ms
60	Rambler	16,907	4045 ms
61	POWr	39,624	4749 ms
62	Esri ArcGIS	3,412	5570 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	153,857	151 ms
2	Dealer	2,332	335 ms
3	Civic	6,533	351 ms
4	Salesforce Commerce Cloud	4,001	372 ms
5	Typepad	1,099	412 ms
6	WordPress	311,129	645 ms
7	Shopify	308,407	759 ms
8	Global-e	1,201	772 ms
9	Ecwid	5,521	873 ms
10	Rackspace	1,880	1264 ms
11	Tilda	69,936	1316 ms
12	Hatena Blog	43,307	1999 ms
13	Webflow	36,763	3603 ms
14	Squarespace	236,228	3642 ms
15	WebsiteBuilder.com	4,817	4384 ms
16	Wix	447,776	4780 ms
17	Weebly	66,212	5814 ms

Marketing

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

Rank	Name	Usage	Average Impact
1	Albacross	1,344	65 ms
2	Madison Logic	1,670	74 ms
3	DemandBase	2,209	126 ms
4	Convertful	1,556	159 ms
5	RD Station	21,042	306 ms
6	Listrak	1,204	381 ms
7	OptinMonster	2,592	410 ms
8	Mailchimp	47,204	465 ms
9	Sojern	4,030	482 ms
10	Wishpond Technologies	1,698	516 ms
11	Hubspot	147,791	523 ms
12	iZooto	2,302	628 ms
13	Yotpo	27,061	630 ms
14	Kargo	1,602	672 ms
15	PureCars	1,813	735 ms
16	KARTE	1,755	898 ms
17	Judge.me	28,108	975 ms
18	Beeketing	2,144	1007 ms
19	Wunderkind	1,249	1336 ms
20	Sumo	11,786	1433 ms
21	Bigcommerce	19,744	2258 ms
22	Drift	5,811	4284 ms
23	Tray Commerce	13,869	4626 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	SnapEngage	1,000	111 ms
2	iPerceptions	5,939	133 ms
3	Help Scout	4,484	139 ms
4	Foursixty	1,325	202 ms
5	LiveTex	1,836	202 ms
6	WebEngage	2,150	240 ms
7	Pure Chat	3,261	330 ms
8	Tawk.to	110,838	369 ms
9	Smartsupp	21,642	402 ms
10	Comm100	1,031	448 ms
11	Jivochat	55,524	637 ms
12	LivePerson	2,795	688 ms
13	Intercom	32,751	1100 ms
14	Tidio Live Chat	25,353	1183 ms
15	Olark	6,739	1320 ms
16	ZenDesk	76,280	1442 ms
17	LiveChat	39,613	1580 ms
18	Dynamic Yield	1,860	1943 ms
19	Freshchat	6,686	3069 ms

Content & Publishing

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

Rank	Name	Usage	Average Impact
1	Spotify	11,016	1 ms
2	OpenTable	4,206	78 ms
3	TripAdvisor	2,018	88 ms
4	Accuweather	1,554	169 ms
5	SnapWidget	13,527	179 ms
6	Tencent	7,169	249 ms
7	Booking.com	1,656	417 ms
8	Cloudinary	2,554	494 ms
9	CPEx	1,137	504 ms
10	Revcontent	1,225	864 ms
11	Hotmart	4,014	926 ms
12	AMP	88,558	1054 ms
13	Embedly	10,428	1401 ms
14	issuu	2,692	1957 ms
15	SoundCloud	6,033	2479 ms
16	Dailymotion	5,423	8720 ms
17	Medium	19,673	12053 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	Google Fonts	220,602	0 ms
2	Bootstrap CDN	31,394	55 ms
3	FontAwesome CDN	310,436	219 ms
4	Monotype	3,294	222 ms
5	Microsoft Hosted Libs	19,679	225 ms
6	Akamai	9,228	297 ms
7	Adobe TypeKit	102,866	340 ms
8	Fort Awesome	3,769	348 ms
9	jQuery CDN	713,886	382 ms
10	Cloudflare CDN	618,006	514 ms
11	JSDelivr CDN	348,981	635 ms
12	Azure Web Services	43,334	677 ms
13	Unpkg	138,968	976 ms
14	Google CDN	3,340,383	1058 ms
15	Yandex CDN	172,717	1715 ms
16	CreateJS CDN	4,377	2936 ms

Tag Management

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

Rank	Name	Usage	Average Impact
1	Adobe Tag Manager	183,984	185 ms
2	Yahoo! Tag Manager	9,086	225 ms
3	TagCommander	1,455	286 ms
4	Ensighten	3,033	545 ms
5	Tealium	27,489	556 ms
6	Google Tag Manager	7,862,343	708 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	1,701	176 ms
2	Optanon	114,644	441 ms
3	Usercentrics CMP	47,735	1018 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	12,856	39 ms
2	ReadSpeaker	5,346	106 ms
3	ResponsiveVoice	6,401	121 ms
4	Polyfill service	1,293	209 ms
5	Browsealoud	1,874	304 ms
6	Amazon Web Services	104,820	375 ms
7	Heroku	14,127	1074 ms
8	Calendly	4,007	1563 ms
9	uLogin	1,427	2923 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
Google Tag Manager	7,862,343	5,570,434 s	708 ms
YouTube	962,443	4,803,260 s	4991 ms
Google CDN	3,340,383	3,534,531 s	1058 ms
Google/Doubleclick Ads	1,172,494	3,480,534 s	2968 ms
Wix	447,776	2,140,310 s	4780 ms
Facebook	3,181,086	1,232,848 s	388 ms
Yandex Metrica	596,366	1,132,490 s	1899 ms
Other Google APIs/SDKs	2,358,410	891,484 s	378 ms
Squarespace	236,228	860,388 s	3642 ms
Google Maps	1,214,682	768,992 s	633 ms
Twitter	331,511	724,490 s	2185 ms
Google Analytics	4,492,386	507,048 s	113 ms
Vimeo	141,109	401,820 s	2848 ms
Weebly	66,212	384,979 s	5814 ms
Pubmatic	221,339	370,370 s	1673 ms
Cloudflare CDN	618,006	317,591 s	514 ms
Yandex CDN	172,717	296,239 s	1715 ms
jQuery CDN	713,886	272,882 s	382 ms
Medium	19,673	237,122 s	12053 ms
Shopify	308,407	234,053 s	759 ms
JSDelivr CDN	348,981	221,626 s	635 ms
Rubicon Project	220,488	219,220 s	994 ms
Hotjar	331,044	218,861 s	661 ms
WordPress	311,129	200,823 s	645 ms
POWr	39,624	188,155 s	4749 ms
Stripe	127,044	143,964 s	1133 ms
Unpkg	138,968	135,670 s	976 ms
Webflow	36,763	132,439 s	3603 ms
Clarity	338,320	121,291 s	359 ms
GoDaddy	122,066	114,510 s	938 ms
ZenDesk	76,280	110,014 s	1442 ms
TikTok	215,993	98,799 s	457 ms
AMP	88,558	93,307 s	1054 ms
Tilda	69,936	92,012 s	1316 ms
Klaviyo	142,926	89,711 s	628 ms
Hatena Blog	43,307	86,574 s	1999 ms
Wistia	26,714	85,121 s	3186 ms
Hubspot	147,791	77,360 s	523 ms
Rambler	16,907	68,383 s	4045 ms
FontAwesome CDN	310,436	67,992 s	219 ms
WordAds	102,326	66,936 s	654 ms
Tray Commerce	13,869	64,152 s	4626 ms
LiveChat	39,613	62,598 s	1580 ms
New Relic	234,387	61,136 s	261 ms
VK	24,107	57,032 s	2366 ms
LiveJournal	9,526	55,586 s	5835 ms
Cookiebot	171,303	52,714 s	308 ms
Sentry	89,800	51,840 s	577 ms
Amazon Ads	178,313	51,283 s	288 ms
Optanon	114,644	50,519 s	441 ms
PayPal	56,797	49,905 s	879 ms
Tumblr	17,786	49,877 s	2804 ms
Usercentrics CMP	47,735	48,617 s	1018 ms
Dailymotion	5,423	47,289 s	8720 ms
Bigcommerce	19,744	44,589 s	2258 ms
Cloudflare	348,270	43,646 s	125 ms
Tawk.to	110,838	40,919 s	369 ms
Kakao	63,733	40,901 s	642 ms
Mediavine	9,730	39,901 s	4101 ms
Amazon Web Services	104,820	39,268 s	375 ms
Intercom	32,751	36,035 s	1100 ms
Taboola	50,480	36,029 s	714 ms
Jivochat	55,524	35,373 s	637 ms
Adobe TypeKit	102,866	34,926 s	340 ms
Adobe Tag Manager	183,984	33,980 s	185 ms
Tynt	162,031	33,579 s	207 ms
iubenda	93,812	33,363 s	356 ms
Yahoo! JAPAN Ads	53,919	30,387 s	564 ms
ShareThis	88,925	30,084 s	338 ms
Tidio Live Chat	25,353	30,004 s	1183 ms
Azure Web Services	43,334	29,328 s	677 ms
Yandex APIs	44,655	27,736 s	621 ms
Judge.me	28,108	27,415 s	975 ms
Skimbit	81,338	26,509 s	326 ms
Drift	5,811	24,893 s	4284 ms
Smart AdServer	109,986	23,453 s	213 ms
Blogger	153,857	23,258 s	151 ms
Media.net	93,229	22,748 s	244 ms
Mailchimp	47,204	21,956 s	465 ms
WebsiteBuilder.com	4,817	21,119 s	4384 ms
Freshchat	6,686	20,523 s	3069 ms
Snapchat	49,940	19,609 s	393 ms
Criteo	165,842	19,584 s	118 ms
LinkedIn Ads	187,285	19,550 s	104 ms
Esri ArcGIS	3,412	19,004 s	5570 ms
MGID	9,908	18,983 s	1916 ms
Pinterest	131,399	18,944 s	144 ms
Yotpo	27,061	17,045 s	630 ms
OneSignal	66,991	16,995 s	254 ms
Sumo	11,786	16,885 s	1433 ms
ID5 Identity Cloud	65,666	15,838 s	241 ms
Tealium	27,489	15,289 s	556 ms
Fastly	9,099	15,278 s	1679 ms
Heroku	14,127	15,176 s	1074 ms
Accessibe Accessibility Overlay	48,040	15,015 s	313 ms
SoundCloud	6,033	14,955 s	2479 ms
Embedly	10,428	14,605 s	1401 ms
Yahoo! Ad Exchange	4,858	14,446 s	2974 ms
Brightcove	13,124	14,337 s	1092 ms
Optimizely	15,596	13,368 s	857 ms
Instagram	10,222	12,875 s	1260 ms
CreateJS CDN	4,377	12,852 s	2936 ms
Mapbox	19,297	12,804 s	663 ms
Integral Ad Science	15,169	12,543 s	827 ms
Privy	19,432	12,293 s	633 ms
Lucky Orange	14,012	11,647 s	831 ms
Hexton	32,051	11,298 s	352 ms
Quantcast	68,514	11,252 s	164 ms
PIXNET	15,360	10,897 s	709 ms
Trust Pilot	44,933	10,774 s	240 ms
Infolinks	5,954	10,412 s	1749 ms
Segment	27,196	10,055 s	370 ms
Adroll	31,186	9,998 s	321 ms
Crazy Egg	20,553	9,970 s	485 ms
Geniee	14,510	9,883 s	681 ms
FullStory	13,438	9,730 s	724 ms
AddToAny	66,597	9,718 s	146 ms
Crowd Control	70,113	9,656 s	138 ms
Cookie-Script.com	41,414	9,397 s	227 ms
Sizmek	5,738	9,060 s	1579 ms
Olark	6,739	8,896 s	1320 ms
Smartsupp	21,642	8,700 s	402 ms
Snowplow	59,526	8,251 s	139 ms
Google reCAPTCHA	27,115	8,234 s	304 ms
AudienceSearch	51,541	8,028 s	156 ms
Inspectlet	5,338	7,841 s	1469 ms
fluct	22,281	7,606 s	341 ms
Baidu Analytics	33,318	7,572 s	227 ms
CallRail	28,866	7,122 s	247 ms
Amplitude Mobile Analytics	36,223	7,074 s	195 ms
Supership	18,113	6,861 s	379 ms
Bing Ads	45,421	6,651 s	146 ms
Twitch	1,450	6,551 s	4518 ms
SocialShopWave	4,310	6,469 s	1501 ms
Google Optimize	41,792	6,445 s	154 ms
RD Station	21,042	6,440 s	306 ms
LiveRamp Privacy Manager	18,855	6,397 s	339 ms
OptiMonk	10,492	6,365 s	607 ms
Trusted Shops	17,034	6,281 s	369 ms
Calendly	4,007	6,261 s	1563 ms
Nielsen NetRatings SiteCensus	17,440	6,016 s	345 ms
DoubleVerify	4,740	5,550 s	1171 ms
StatCounter	51,587	5,371 s	104 ms
Twitter Online Conversion Tracking	68,128	5,356 s	79 ms
Bugsnag	13,395	5,319 s	397 ms
issuu	2,692	5,268 s	1957 ms
LinkedIn	17,125	5,244 s	306 ms
Bold Commerce	11,923	5,184 s	435 ms
Conversant	46,153	5,168 s	112 ms
VWO	8,018	5,119 s	639 ms
Heap	13,234	4,991 s	377 ms
Ecwid	5,521	4,818 s	873 ms
LongTail Ad Solutions	6,143	4,766 s	776 ms
Adyen	2,322	4,765 s	2052 ms
Pendo	13,333	4,757 s	357 ms
Attentive	9,166	4,708 s	514 ms
Microsoft Hosted Libs	19,679	4,421 s	225 ms
Technorati	22,378	4,311 s	193 ms
uLogin	1,427	4,171 s	2923 ms
VigLink	6,674	4,146 s	621 ms
Forter	4,345	4,097 s	943 ms
Scorecard Research	46,696	4,065 s	87 ms
Yandex Ads	8,817	4,055 s	460 ms
Moat	3,861	4,011 s	1039 ms
Index Exchange	33,560	3,974 s	118 ms
reddit	16,277	3,875 s	238 ms
Signyfyd	2,567	3,839 s	1495 ms
AppNexus	177,948	3,835 s	22 ms
Dynatrace	3,420	3,835 s	1121 ms
Seedtag	2,513	3,783 s	1505 ms
Hotmart	4,014	3,718 s	926 ms
WordPress Site Stats	64,925	3,615 s	56 ms
Dynamic Yield	1,860	3,614 s	1943 ms
LINE Corporation	24,991	3,437 s	138 ms
LoyaltyLion	4,213	3,434 s	815 ms
AdScore	4,378	3,374 s	771 ms
Mixpanel	20,441	3,329 s	163 ms
Affirm	6,594	3,294 s	500 ms
IPONWEB	19,682	3,236 s	164 ms
ContentSquare	3,541	3,229 s	912 ms
mPulse	32,660	3,196 s	98 ms
GumGum	123,913	3,128 s	25 ms
AppDynamics	3,419	3,100 s	907 ms
Disqus	1,135	3,092 s	2724 ms
GitHub	6,970	3,026 s	434 ms
Intercept Interactive	18,824	3,004 s	160 ms
Akamai	9,228	2,740 s	297 ms
Sonobi	54,964	2,739 s	50 ms
Luigis Box	2,210	2,690 s	1217 ms
fam	747	2,660 s	3561 ms
WisePops	2,044	2,536 s	1241 ms
Gigya	2,032	2,525 s	1243 ms
LightWidget	11,137	2,513 s	226 ms
Secomapp	2,220	2,446 s	1102 ms
33 Across	143,025	2,443 s	17 ms
SnapWidget	13,527	2,415 s	179 ms
Outbrain	11,439	2,405 s	210 ms
Matomo	12,297	2,396 s	195 ms
Rackspace	1,880	2,377 s	1264 ms
Gemius	15,825	2,360 s	149 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.