TidyToolsDomain Authority Index · data of

Domain authority

si.edu domain authority

si.edu has a domain authority score of 72 out of 100 (high), based on 65,690 referring domains and a web graph rank of 1,522 among 133 million domains; its traffic rank is Top 10K websites (Chrome).

72 / 100
65,690
referring domains (backlinks from other domains)
#1,522
web graph rank of 133,241,980 domains
Top 10K
Chrome real-user traffic bucket

All metrics for si.edu

Authority score72 / 100
Referring domains65,690
Web graph rank (harmonic centrality)#1,522 (top 0.01%)
PageRank position#1,339
Subdomains seen in the crawl728
Majestic Million rank#475
Majestic referring subnets / IPs24,940 / 55,437
Traffic rankTop 10K websites (Chrome)
Position by authority in our top 20,000#566

How the authority score is calculated

The score is the average of two parts, each from 0 to 100:

For this domain: rank part 74.2 (web graph rank 1,522 of 133,241,980), link part 68.8 (65,690 referring domains), average 71.5, rounded to 72.

It is consistent across all 120 million domains in the data, so it is good for ranking and filtering lists. It is not Moz Domain Authority or Ahrefs Domain Rating. Referring domains count other domains that link to this one, not individual backlinks; no list of linking pages is included.

Domains with a similar authority score

#DomainAuthorityReferring domainsWeb graph rankTraffic rank
562coursera.org7267,240968Top 5K websites (Chrome)
563buzzfeed.com7266,415956Top 5K websites (Chrome)
564webflow.io7266,1971,069Top 500K websites (Chrome)
565podbean.com7266,1961,442Top 500K websites (Chrome)
567mailerlite.com7264,657985Top 50K websites (Chrome)
568buzzsprout.com7264,2391,426Top 500K websites (Chrome)
569pnas.org7262,8141,197Top 100K websites (Chrome)
570google.nl7262,1991,163Top 50K websites (Chrome)

AI crawler policy

AI crawler policy: Open. GPTBot is allowed, ClaudeBot is allowed and PerplexityBot is allowed in its robots.txt (checked 2026-10-02). Does si.edu block GPTBot? →

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FAQ

What is the domain authority of si.edu?
si.edu has a domain authority score of 72 out of 100 (high), based on 65,690 referring domains and a web graph rank of 1,522 among 133 million domains; its traffic rank is Top 10K websites (Chrome). The score is our own open-data metric (0-100) and is not Moz Domain Authority or Ahrefs Domain Rating.
How many backlinks does si.edu have?
si.edu is linked to from 65,690 other domains in the Common Crawl web graph (release cc-main-2026-jul-aug-sep). This counts referring domains, not individual backlinks, and Common Crawl does not see the whole web, so commercial tools that crawl more will show larger numbers.
How does si.edu rank among all websites?
Its web graph rank (harmonic centrality) is 1,522 out of 133,241,980 ranked domains, which puts it in the top 0.01%. Its PageRank position is 1,339. Majestic Million ranks it #475.
Is the si.edu authority score the same as Moz DA or Ahrefs DR?
No. It is an independent score computed from open data (Common Crawl, Majestic Million, Chrome UX Report). It is consistent across all domains, so it works for comparing and filtering sites, but the numbers will not match the commercial tools.