Infrastructure
· 9 checks — DNS, redirects, IPv6, crawlability, URL variants, and domain intelligence rolled into one auditable list.BRedirect Chain2 redirect(s), 102 ms totalREVIEW
https://columbia.edu
41 ms · HTTP/1.1
http://www.columbia.edu/
17 ms · HTTP/1.1
https://www.columbia.edu
44 ms · HTTP/1.1 FINAL
| # | URL | Status | Time | Protocol | Server |
|---|---|---|---|---|---|
| 1 | https://columbia.edu | 301 | 41 ms | HTTP/1.1 | cloudflare |
| 2 | http://www.columbia.edu/ | 302 | 17 ms | HTTP/1.1 | cloudflare |
| 3 | https://www.columbia.edu | 200 | 44 ms | HTTP/1.1 | cloudflare |
See the visual redirect chain in the HTTP Probe tab →
Each redirect adds latency. Try to minimize the chain to 1 hop.
Redirect chain — each hop adds latency; combine into one redirect where possible.
Source: Google Search Central / web.dev
Redirect directly from https://columbia.edu to https://www.columbia.edu
Redirect chain could be flattened to one hop — server config tweak removes intermediate latency.
Source: web.dev
If permanent, use 301 instead.
302 (Found) is for genuinely temporary redirects — if this redirect is permanent, switch to 301 to preserve SEO equity.
Learn more ▾ ▴
Search engines treat 302 as temporary, keeping the original URL indexed and not transferring full link equity to the destination. Use 301 (Moved Permanently) for permanent redirects (HTTP→HTTPS, www-vs-non-www, URL restructures).
Source: Google Search Central
CIPv6 ReadinessActionNo IPv6 supportREVIEW
IPv6 support is increasingly important for global accessibility. About 40% of internet users have IPv6 connectivity.
No AAAA records — same impact as 'no IPv6 (AAAA) records'; IPv6-preferring clients pay extra latency falling back to IPv4.
Source: Google IPv6 stats
BCrawlabilityno robots.txt, no sitemapREVIEW
robots.txt is optional but recommended. It tells search engine crawlers which pages to index.
No robots.txt — crawlers fetch /robots.txt and get 404; not breaking but means default crawl behavior with no directives or sitemap reference.
Learn more ▾ ▴
A minimal robots.txt with `User-agent: * / Allow: / / Sitemap: https://example.com/sitemap.xml` covers the basics. Without it, crawlers behave fine but lose the sitemap signal and can't be selectively blocked from crawl-traps.
Source: robotstxt.org
A sitemap helps search engines discover and index your pages more efficiently.
No sitemap.xml — Google relies on crawl-graph discovery alone, slowing indexing of deep or fresh URLs.
Learn more ▾ ▴
A sitemap accelerates Google's discovery of new and updated content. Most CMSes auto-generate one; static-site frameworks need a build-step plugin. Reference it from robots.txt and submit in Search Console to confirm Google can fetch it.
Source: sitemaps.org / Google Search Central
No robots.txt found
This is fine for most sites — a missing robots.txt allows all crawling by default.
No sitemap found
Adding a sitemap helps search engines discover your pages.
BURL Variantswww/non-www, trailing slash, HTTP→HTTPSREVIEW
www / non-www
HTTP → HTTPS
HTTP version does not redirect to HTTPS
BTLS Certificate Expiry & Recommendations84 days until leaf cert expires — 4 issues to addressREVIEW
Certificate validity
Recommended actions
- Extend HSTS max-age to at least 31536000 (1 year) to meet the preload list criteria
- Add includeSubDomains to the HSTS directive
- Enable DNSSEC on your domain for DNS spoofing protection
- Enable OCSP stapling on your TLS server to remove a CA roundtrip and protect user privacy
A+DNS Records2 A records, 14 ms lookupPASS
| A | 162.159.138.64, 162.159.128.65 |
| AAAA | — |
| CNAME | — |
| NS | auth1.dns.cogentco.com, ns1.lse.ac.uk, ext-ns1.columbia.edu, auth2.dns.cogentco.com |
| MX | 10 mxb-00364e01.gslb.pphosted.com 10 mxa-00364e01.gslb.pphosted.com |
| TXT | atlassian-domain-verification=3a/aVmiVzaMOzlhAodx3n7lmq1cDotGOHNI3ehzFLzgN7YLZEB... SPF v=spf1 include:%{ir}.%{v}.%{d}.spf.has.pphosted.com ~all anthropic-domain-verification-01mqc0=QYIx6Pw50pyhbeOfqjhRRNpve asv=c2f28d3e6fab94ed285140f6a7a2f595 00DVG000008EUsr=1TBVG0000000K0L 00D36000000XoHU=1TBUw00000001fF MS=ms88535648 google-site-verification=79W02b1NsvPOhVkXxG5gXzAXuxuYquPTXmx_l6KfRok MS=ms32107722 docusign=abbafadf-a495-4889-935f-5fdac37be903 docusign=f8b82e15-b287-46b9-9729-a7436d71c422 adobe-idp-site-verification=c4c82a5f2bf3cc3ee4ad2ee246c28e17ead150faf152556bc9ca... google-site-verification=B93x40FIZF4LI-5cayepjvuwU8ZodIQ09zIDG1gHtIc apple-domain-verification=6W1ObUreaMieGziS fastly-domain-delegation-UzZdOKwpsuzDObCLhWK0-12292020 fastly-domain-delegation-columbia-323594-2020-12-07 ZOOM_verify_H76gKGnfTfSjo0uBs3ATpw ZOOM_verify_aIBp_UI9RA-_nAc54T9CiA ZOOM_verify_ohdpGstzTlO2gNsWqnSiHQ ZOOM_verify_ZJlClnqsRTqo4L8EQGaPDg ZOOM_verify__tMWR0IkQ5mSUFNi7PT0-A wpe-verification=cssrsprod ca3-154a83c0e9b44fa094af06b7a8c9f489 rm_verify=cf192bfd71 intersight=f68fd98601fae5dcfd60cd38f9df964367f5e3ebe94f0cc148eec13f7e11d7e6 ca3-018df5b7d38b415fbe9c920d89e3e815 atlassian-domain-verification=TGY4izz2FIXsrTR48IJgpJMfixggF0xpHJ4TC91Ii5DqZYvIR3... MS=ms94259742 openai-domain-verification=dv-coLwtcZeuA8rWCUFNhz21TTz google-site-verification=6m_FjnmBT3E6N2cHMf6NxPjSVoWbq4IcRYNlAKT1Dzw wpe-verification=ncdpcolumbia |
| CAA | Lookup not available with standard resolver |
CAA record lookup requires a specialized DNS resolver. This check will be available in a future update.
Informational: CAA (Certification Authority Authorization) records weren't checked in this scan.
A+Domain Intelligencecolumbia.edu — 41 years, 4 months old, hosted on CloudflarePASS
381 days
July 31, 2027
84 days
Issued by Google Trust Services
41 years, 4 months
Registered July 5, 1985
Status unknown
Protects against DNS spoofing
Cloudflare
ASN AS13335
162.159.138.64
Registrar unknown