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https://princeton.edu

Infrastructure

· 9 checks — DNS, redirects, IPv6, crawlability, URL variants, and domain intelligence rolled into one auditable list.
SCORE
81
GRADE
B
FIX
2
REVIEW
2
PASS
5
INFO
0
Probed from Madrid, Spain
302 Found
Checks
9
5 PASS 2 REVIEW 2 FIX
D
URL Variants
Action
www/non-www, trailing slash, HTTP→HTTPS
FIX
www/non-www, trailing slash, HTTP→HTTPS
Critical::
Both www and non-www versions serve content
Got: Both variants return 200 Expected: One variant 301-redirects to the other
Critical::
HTTP version does not redirect to HTTPS
Got: HTTP 302 Expected: 301 redirect to HTTPS

www / non-www

200https://www.princeton.edu/
200https://princeton.edu/

Inconsistent — duplicate content risk

HTTP → HTTPS

302http://princeton.edu/ → http://www.Princeton.EDU/

HTTP version does not redirect to HTTPS

D
CDN & Delivery
Action
No CDN detected
FIX
No CDN detected
Warning::
No CDN detected
A CDN can significantly improve load times for users around the world by caching content at edge nodes closer to them.
No CDN detected

Consider using a CDN to improve global delivery speed and reduce origin load.

C
IPv6 Readiness
Action
No IPv6 support
REVIEW
No IPv6 support
Info::
No IPv6 (AAAA) records found
IPv6 support is increasingly important for global accessibility. About 40% of internet users have IPv6 connectivity.
No IPv6 Support
About 40% of internet users have IPv6. Consider adding AAAA records.

IPv6 support is increasingly important for global accessibility. About 40% of internet users have IPv6 connectivity.

Why this matters

No AAAA records — same impact as 'no IPv6 (AAAA) records'; IPv6-preferring clients pay extra latency falling back to IPv4.

Source: Google IPv6 stats

B
TLS Certificate Expiry & Recommendations
52 days until leaf cert expires — 4 issues to address
REVIEW

Certificate validity

52
days left
0d 30d 60d 90d+

Recommended actions

  • Prefer TLS 1.3 — TLS 1.2 is acceptable but TLS 1.3 removes RSA key exchange and improves latency
  • Enable HSTS: Strict-Transport-Security: max-age=31536000; includeSubDomains
  • 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 Records
1 A records, 29 ms lookup
PASS
1 A records, 29 ms lookup
Info::
Resolves to 1 IPv4 address(es)
Got: 140.180.223.22
Info::
Single A record — no DNS redundancy
Multiple A records provide failover if one server goes down.
Info::
No IPv6 (AAAA) records
Info::
9 nameserver(s) configured
Got: ns5.dnsmadeeasy.com, a20-65.akam.net, a6-64.akam.net, a24-66.akam.net, a1-158.akam.net, ns7.dnsmadeeasy.com, a7-65.akam.net, ns6.dnsmadeeasy.com, a3-67.akam.net
Info::
1 mail exchanger(s) configured
Info::
CAA records not checked
CAA record lookup requires a specialized DNS resolver. This check will be available in a future update.
Info::
SPF record present in TXT
Info::
DNS resolution time: 29 ms
Got: 29 ms
A140.180.223.22
AAAA—
CNAME—
NSns5.dnsmadeeasy.com, a20-65.akam.net, a6-64.akam.net, a24-66.akam.net, a1-158.akam.net, ns7.dnsmadeeasy.com, a7-65.akam.net, ns6.dnsmadeeasy.com, a3-67.akam.net
MX
10 princeton-edu.mail.protection.outlook.com
TXT
google-site-verification=9spyuhtdpgltj4ba6qol87mlltsvqwtwpfpjckhxuaa
apple-domain-verification=M2IB2C41pkMXfS91
adobe-idp-site-verification=73f4a96f-50ca-4b7f-858e-6cef4af902aa
docusign=9b74122b-7e36-4311-9fd4-a1f8200928a9
paloaltonetworks-site-verification=fb3d98b6d82f4593542f655e32a264fe763b0b1ce0a80...
SPF v=spf1 include:%{ir}.%{v}.%{d}.spf.has.pphosted.com ~all
kwaacu+go+erbui7ikfpg6udfqlprkz9e2pxxeafjplnmhnkyjnfg0uokvami2f8iz7qet4dr+j8ou3/...
airtable-verification=f404295b37024f7747d2de8944a93fee
google-site-verification=fxbfrfkt_fmpamiadsiqhygwsrxgcfsmxpkveva7bhk
verifying for Netlify support case #19507
ms=ms98806852
R6TEJ9GJ2ECTYPQRT0T76RZIKOG4TQV1Z6TD75P33
jamf-site-verification=gOHFT5mfGhE1m6aC3XEdag
57dmsH4y22BIE+OMFrnNvGtt3xyyh2Z/XhvRbQfkhMSIMh88zNcjCr/Bj0nOzrEDguiuGBxFOcYuCiw5...
atlassian-domain-verification=uT+jiLnKmr+CvFxx3GGJaEAobMxLzqz6Kl+AO4ha-HGmEtTXui...
dropbox-domain-verification=xf71iopc45pc
github-verification=fRwTRsEqERcBV3GgKMdt4RYrb8CWTfLrN72Z5WdW
docusign=8ee25fec-197b-476d-9659-5a3717059bc0
CAALookup not available with standard resolver
Resolved in 29 ms

Multiple A records provide failover if one server goes down.

Why this matters

Single A record means a single point of failure — if that IP goes down, your site is unreachable until DNS TTL expires.

Learn more ▾

Add multiple A records for round-robin failover, or use a managed DNS provider with health-checked failover (Route 53, Cloudflare, NS1). Short TTL (60-300s) lets clients recover faster on outages.

Source: SRE practice / DNS architecture

CAA record lookup requires a specialized DNS resolver. This check will be available in a future update.

Why this matters

Informational: CAA (Certification Authority Authorization) records weren't checked in this scan.

A
Redirect Chain
1 redirect(s), 589 ms total
PASS
1 redirect(s), 589 ms total
Info::
Single redirect
Got: https://princeton.edu → https://www.Princeton.EDU/ (302)
Info::
WWW normalization redirect
Info::
Uses 302 (temporary) redirect
If permanent, use 301 instead.
Got: https://princeton.edu
Info::
Redirect overhead: 589 ms total
Got: 589 ms

https://princeton.edu

488 ms · HTTP/1.0

302

https://www.Princeton.EDU/

101 ms · HTTP/1.1 FINAL

#URLStatusTimeProtocolServer
1https://princeton.edu302488 msHTTP/1.0BigIP
2https://www.Princeton.EDU/200101 msHTTP/1.1cloudflare

See the visual redirect chain in the HTTP Probe tab →

If permanent, use 301 instead.

Why this matters

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

A+
Crawlability
robots.txt present, sitemap with 14 URLs
PASS
robots.txt present, sitemap with 14 URLs
Info::
robots.txt is present
Got: 2275 bytes
Info::
sitemap.xml is present
Info::
sitemap.xml is valid XML
Info::
sitemap.xml contains 14 entries
Info::
Sitemap index with 14 child sitemaps
Info::
robots.txt does not reference a sitemap
Add a 'Sitemap:' directive to robots.txt so search engines can discover your sitemap.

Add a 'Sitemap:' directive to robots.txt so search engines can discover your sitemap.

Why this matters

robots.txt omits Sitemap: directive — crawlers must fetch /sitemap.xml by convention; reliable but missing the explicit hint.

Source: sitemaps.org

robots.txt 200 OK
Size 2275 B Sitemaps referenced 0 User-agents * Blocking No — crawling allowed
#
# robots.txt
#
# This file is to prevent the crawling and indexing of certain parts
# of your site by web crawlers and spiders run by sites like Yahoo!
# and Google. By telling these "robots" where not to go on your site,
# you save bandwidth and server resources.
#
# This file will be ignored unless it is at the root of your host:
# Used:    http://example.com/robots.txt
# Ignored: http://example.com/site/robots.txt
#
# For more information about the robots.txt standard, see:
# http://www.robotstxt.org/robotstxt.html

User-agent: *
# CSS, JS, Images
Allow: /core/*.css$
Allow: /core/*.css?
Allow: /core/*.js$
Allow: /core/*.js?
Allow: /core/*.gif
Allow: /core/*.jpg
Allow: /core/*.jpeg
Allow: /core/*.png
Allow: /core/*.svg
Allow: /profiles/*.css$
Allow: /profiles/*.css?
Allow: /profiles/*.js$
Allow: /profiles/*.js?
Allow: /profiles/*.gif
Allow: /profiles/*.jpg
Allow: /profiles/*.jpeg
Allow: /profiles/*.png
Allow: /profiles/*.svg
# Directories
Disallow: /core/
Disallow: /profiles/
# Files
Disallow: /README.md
Disallow: /composer/Metapackage/README.txt
Disallow: /composer/Plugin/ProjectMessage/README.md
Disallow: /composer/Plugin/Scaffold/README.md
Disallow: /composer/Plugin/VendorHardening/README.txt
Disallow: /composer/Template/README.txt
Disallow: /modules/README.txt
Disallow: /sites/README.txt
Disallow: /themes/README.txt
Disallow: /web.config
# Paths (clean URLs)
Disallow: /admin/
Disallow: /comment/reply/
Disallow: /filter/tips
Disallow: /node/add/
Disallow: /search/
Disallow: /user/register
Disallow: /user/password
Disallow: /user/login
Disallow: /user/logout
Disallow: /media/oembed
Disallow: /*/media/oembed
# Paths (no clean URLs)
Disallow: /index.php/admin/
Disallow: /index.php/comment/reply/
Disallow: /index.php/filter/tips
Disallow: /index.php/node/add/
Disallow: /index.php/search/
Disallow: /index.php/user/password
Disallow: /index.php/user/register
Disallow: /index.php/user/login
Disallow: /index.php/user/logout
Disallow: /index.php/media/oembed
Disallow: /index.php/*/media/oembed

# Pager links. All the stuff we want paginated is already exposed
# in the XML sitemap. No need to crawlers to waste time going thru
# the news and events pagers.
Disallow: /*?page=
Disallow: /*&page=

# Search with keys
Disallow: /search?search=
sitemap.xml 200 OK
Type Sitemap Index URLs 14 entries Valid XML Yes
Child Sitemaps:
A+
Domain Intelligence
princeton.edu — 39 years, 7 months old, hosted on PRINCETON-AS - Princeton University, US
PASS
princeton.edu — 39 years, 7 months old, hosted on PRINCETON-AS - Princeton University, US
Info::
Domain registered until Jul 31, 2027 (1 years, 3 months remaining)
Info::
Hosting: PRINCETON-AS - Princeton University, US
Got: AS88
Domain expiry

382 days

July 31, 2027

SSL certificate

52 days

Issued by Internet2

Domain age

39 years, 7 months

Registered April 3, 1987

DNSSEC

Status unknown

Protects against DNS spoofing

Hosting

PRINCETON-AS - Princeton University, US

ASN AS88

140.180.223.22

Registrar

Registrar unknown

Lock status unknown 9 NS records
Expiry timeline
Today
+1 year
Domain expiry SSL expiry Danger zone (≤30 days)
Registrar
Created April 3, 1987 (39 years, 7 months ago)
Expires July 31, 2027 (1 years, 3 months)
Last Updated April 8, 2026
Name Servers a7-65.akam.net, ns6.dnsmadeeasy.com, a1-158.akam.net, a24-66.akam.net, a6-64.akam.net, a3-67.akam.net, a20-65.akam.net, ns5.dnsmadeeasy.com, ns7.dnsmadeeasy.com
Registrant Princeton University
Hosting
IP Address 140.180.223.22
ASN AS88 (PRINCETON-AS - Princeton University, US)
Provider PRINCETON-AS - Princeton University, US
Data source: whois (1.0s)
A
HTTP Probe Timing
Total 554 ms — DNS, TCP, TLS, TTFB, content transfer breakdown
PASS
DNS Lookup DNS Lookup — time to resolve the domain name to an IP address.
27 ms
TCP Connect TCP Connect — time to establish a TCP connection to the server.
104 ms
TLS Handshake TLS Handshake — time to complete the HTTPS encryption handshake.
318 ms
Time to First Byte Time to First Byte — how long the server takes to respond with the first byte of data.
554 ms
Total Time Total request time from DNS lookup through full response.
554 ms

Connection waterfall

DNS Lookup 27 ms TCP Connect 104 ms TLS Handshake 318 ms Server Processing 105 ms Content Transfer 0 ms
All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.

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