facebookexternalhit: share of top websites blocking it

On 26 October 2026, 3.6% of the readable top 10k websites fully blocked facebookexternalhit in robots.txt (bounds 2.9% to 23.1% over all 8,220 websites, 1,659 of them unreadable); 3.9% blocked it partly and 5.9% named it.

Last verified 2026-10-26 21:13 UTC (daily run of 2026-10-26). Proof for that day.

Operator
Meta/Facebook
What it is
Ostensibly only for sharing, but likely used as an AI crawler as well
Description
Note that excluding FacebookExternalHit will block incorporating OpenGraph data when sharing in social media, including rich links in Apple's Messages app. According to Meta, its purpose is "to crawl the content of an app or website that was shared on one of Meta’s family of apps…". However, see discussions here and here for evidence to the contrary.
robots.txt token
User-agent: facebookexternalhit
Listed since
2026-10-26 (in this ledger's registry)

Fully blocks

3.6%

236 sites; bounds 2.9% to 23.1%

Partly blocks

3.9%

256 sites

Name it explicitly

5.9%

389 sites; unreadable: 3,439

Over time

Share of panel sites blocking facebookexternalhit4 lines, 2016-09-05 to 2026-10-26; values between 2.30 and 5.32 %; latest 3.60 %.2.062.933.814.685.56Sep 2016Mar 2019Sep 2021Apr 2024Oct 2026blocks, reconstructed (Common Crawl): 2016-09-05 UTC: 3.08 %blocks, reconstructed (Common Crawl): 2017-09-25 UTC: 3.45 %blocks, reconstructed (Common Crawl): 2018-09-24 UTC: 3.58 %blocks, reconstructed (Common Crawl): 2019-09-23 UTC: 2.80 %blocks, reconstructed (Common Crawl): 2020-09-28 UTC: 2.52 %blocks, reconstructed (Common Crawl): 2021-09-27 UTC: 2.58 %blocks, reconstructed (Common Crawl): 2022-10-03 UTC: 2.55 %blocks, reconstructed (Common Crawl): 2024-09-16 UTC: 2.30 %blocks, reconstructed (Common Crawl): 2026-09-21 UTC: 2.39 %partly blocks, reconstructed (Common Crawl): 2016-09-05 UTC: 5.04 %partly blocks, reconstructed (Common Crawl): 2017-09-25 UTC: 4.88 %partly blocks, reconstructed (Common Crawl): 2018-09-24 UTC: 4.79 %partly blocks, reconstructed (Common Crawl): 2019-09-23 UTC: 4.76 %partly blocks, reconstructed (Common Crawl): 2020-09-28 UTC: 4.82 %partly blocks, reconstructed (Common Crawl): 2021-09-27 UTC: 4.98 %partly blocks, reconstructed (Common Crawl): 2022-10-03 UTC: 4.88 %partly blocks, reconstructed (Common Crawl): 2024-09-16 UTC: 5.07 %partly blocks, reconstructed (Common Crawl): 2026-09-21 UTC: 5.32 %blocks, daily observation: 2026-10-26 UTC: 3.60 %partly blocks, daily observation: 2026-10-26 UTC: 3.90 %

"Partly blocks" counts every robots.txt whose rules for facebookexternalhit disallow some paths, including generic rules for all crawlers (for example /search); it is not a measure of targeted AI policy. Shares are of the readable websites (W − U: 8,220 websites, 1,659 unreadable); the bounds assume none / all of the unreadable sites block. Solid: daily first-party observations (top 10k of the Tranco list W3ZV9, one fixed cohort). Dashed: reconstructed from Common Crawl (top 10k, sites readable in every crawl), a separate series.

Reconstructed values per crawl
CrawlDateBlocksSites read
CC-MAIN-2016-362016-09-053.1%3,216
CC-MAIN-2017-392017-09-253.5%3,216
CC-MAIN-2018-392018-09-243.6%3,216
CC-MAIN-2019-392019-09-232.8%3,216
CC-MAIN-2020-402020-09-282.5%3,216
CC-MAIN-2021-392021-09-272.6%3,216
CC-MAIN-2022-402022-10-032.5%3,216
CC-MAIN-2024-382024-09-162.3%3,216
CC-MAIN-2026-392026-09-212.4%3,216

Recent blockers

Sites that started fully blocking facebookexternalhit since 2026-07-28, highest-ranked first.

DateSiteWhat changed
No changes recorded yet. The first daily run is the baseline; changes appear from the second day on.

Recent unblockers

DateSiteWhat changed
No changes recorded yet. The first daily run is the baseline; changes appear from the second day on.

Sites blocking facebookexternalhit now

fbcdn.net · googlevideo.com (*) · baidu.com (*) · reddit.com (*) · skybridge.click (*) · registrar-servers.com (*) · meraki.com (*) · t.co (*) · demdex.net (*) · weibo.com (*) · naver.com (*) · cookiedatabase.org (*) · gcdn.co (*) · kwai.net (*) · edgecdn.ru (*) · netcraze.io (*) · sharethrough.com (*) · hstgr.net (*) · imgsmail.ru (*) · hihonorcloud.com (*) · quantserve.com (*) · creativecdn.com (*) · crwdcntrl.net (*) · vkontakte.ru (*) · sentinelone.net (*) · adform.net (*) · daum.net (*) · tiktokw.us (*) · xiaohongshu.com (*) · btloader.com (*) · namecheaphosting.com (*) · jamfcloud.com (*) · rocketmoney.dev (*) · namu.wiki (*) · leboncoin.fr · themoviedb.org · furaffinity.net · amap.com (*) · stbid.ru (*) · kakao.com (*) · 1mg.com · exhentai.org (*) · aka.ms (*) · firebaseio.com (*) · keirin.jp (*) · sportfilm800.com (*) · ind.xxx (*) · qcloud.com (*) · mparticle.com · adrta.com (*) · wikihow.com · weibo.cn (*) · clevertap-prod.com (*) · salesforceliveagent.com (*) · adsco.re (*) · redditstatic.com (*) · msappproxy.net (*) · sogou.com (*) · tappx.com (*) · secureserver.net (*)

(*) blocked through the * group, not by name. Full list in current.csv.

Cite this

InfraRabbit AI Crawl Ledger, "Share of top websites blocking facebookexternalhit", https://infrarabbit.com/crawlers/bot/facebookexternalhit, retrieved 2026-10-26. CC BY 4.0.