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https://harpercollins.com

Infrastructure

· 9 checks — DNS, redirects, IPv6, crawlability, URL variants, and domain intelligence rolled into one auditable list.
SCORE
86
GRADE
B
FIX
0
REVIEW
3
PASS
6
INFO
0
Probed from Santa Clara, United States
301 Moved Permanently
Checks
9
6 PASS 3 REVIEW
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
URL Variants
www/non-www, trailing slash, HTTP→HTTPS
REVIEW
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
Info::
HTTP correctly 301-redirects to HTTPS

www / non-www

200https://www.harpercollins.com/
200https://harpercollins.com/

Inconsistent — duplicate content risk

HTTP → HTTPS

301http://harpercollins.com/ https://harpercollins.com/

Consistent

B
TLS Certificate Expiry & Recommendations
229 days until leaf cert expires — 5 issues to address
REVIEW

Certificate validity

229
days left
0d 30d 60d 90d+

Recommended actions

  • Extend HSTS max-age to at least 31536000 (1 year) to meet the preload list criteria
  • Add includeSubDomains to the HSTS directive
  • Add the preload directive and submit to hstspreload.org once max-age + includeSubDomains are in place
  • 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, 51 ms lookup
PASS
1 A records, 51 ms lookup
Info::
Resolves to 1 IPv4 address(es)
Got: 23.227.38.65
Info::
Single A record — no DNS redundancy
Multiple A records provide failover if one server goes down.
Info::
No IPv6 (AAAA) records
Info::
2 nameserver(s) configured
Got: dmtu.mt.ns.els-gms.att.net, dbru.br.ns.els-gms.att.net
Info::
2 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: 51 ms
Got: 51 ms
A23.227.38.65
AAAA
CNAME
NSdmtu.mt.ns.els-gms.att.net, dbru.br.ns.els-gms.att.net
MX
5 mxb-00596a01.gslb.pphosted.com
5 mxa-00596a01.gslb.pphosted.com
TXT
nmmBU9m0JKlQMzYMFSA/7LacnfwY0LsGTpiMcOsFM0jILtamuI3jvV2g3+O7KKOWO4rFfGHDmZWIO4IR...
dropbox-domain-verification=ucbh5javnke3
google-site-verification=tyaXIKYYcxrtquGnQyTPzzqgJzO-f3JTYTofj1Pzg8c
adobe-idp-site-verification=42f51b67c9248bf4af00579848be3b6b4165111f7e95fa138083...
/eU+eq5f7XbZNa8X8rWAWZCAxYOy7z4IYhIT2Hp05EahhGMbex3/zdcOQDwWN6QGJr6ECqI6hdg1Tqpr...
webexdomainverification.4C675B8AE253B136E053AB06FC0A3F65=af0d073d-91d2-47fb-afa5...
dbc36a8f57004cec8e50382190a4c767
adobe-sign-verification=f95381908feb7fd54d511615905bee51
knowbe4-site-verification=0694ce74005828dc4bb8b7299bfb6f61
ahrefs-site-verification_73874523a8c99a90479647cc3a4099da8bdd565a9b576542cdf7518...
bugcrowd-verification=a5b82af72ff73e6f057526a8c6946c80
atlassian-domain-verification=uNoIhBXurxzVlQa0FvK2t9Yld5byfvXbFRQaMToGvrieKjBdyl...
_globalsign-domain-verification=bkER3fxZbQLIEl16wZS08EnQpoEG9UQBKihu8Ks2Zd
ZOOM_verify_c8YbePuKRTOlYTGf_XKe2Q
ca3-55817d6452e54bb686ad84dded8965e2
asv=6bcb95b6501de3efbcb4bba9870aa071
docker-verification=dfcc680b-f409-45d1-b9a7-7992e21b9a52
SPF v=spf1 include:%{ir}.%{v}.%{d}.spf.has.pphosted.com ~all
google-site-verification=mrNi0RTTBHQ_NPHcDoUYnii2GYVeN8gg0XIYRMJmoU0
google-site-verification=nmk1hXTEYrIjhNQa3heeK1KiHKtzpXxB1jDCZP7e8o0
ValidationTokenValue=90fe4eb0-f1cb-4e32-a847-dc0e99fd6213
docusign=725b7e74-15db-4d54-ac76-889b6f206549
figma-domain-verification=950abdf37a7ff2b00c3954b0b7c5b529439c5bc172d9955316215e...
yahoo-verification-key=i+M9oi9b5+XYPU48wdxWhYtTSJpnVouSnI3IUqZq88I=
extensis-domain-verification=fb808a86-2bd8-4609-b6da-ee938a0b5625
doordash-verification=N8fQ7KYWS5swsnXabGRKOjeGIighbm
srjf85faf1ivlj2abkt967tdfd
shopify-verification-code=nZBi4zupnooVrmOOmRl9un6F5ZYuq9
gc-ai-domain-verification-ctbrt8=XloEYpi5FPEXK53iCdLQtkSRU
openai-domain-verification=dv-0nFS3ectycyfVyRNeTWKRZz3
figma-domain-verification=2f62cdb936c6fe21e979b91c99c54d82fb999e849a36aa4b2c5d05...
google-site-verification=jBGiywYAcKUeCPqNZsGSvr_C6RMCPh0Z9g73o-1sBVI
CAALookup not available with standard resolver
Resolved in 51 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), 268 ms total
PASS
1 redirect(s), 268 ms total
Info::
Single redirect
Got: https://harpercollins.com → https://www.harpercollins.com/ (301)
Info::
WWW normalization redirect

https://harpercollins.com

191 ms · HTTP/1.1

301

https://www.harpercollins.com/

77 ms · HTTP/1.1 FINAL

#URLStatusTimeProtocolServer
1https://harpercollins.com301191 msHTTP/1.1cloudflare
2https://www.harpercollins.com/20077 msHTTP/1.1cloudflare

See the visual redirect chain in the HTTP Probe tab →

A+
Crawlability
robots.txt present, sitemap with 66 URLs
PASS
robots.txt present, sitemap with 66 URLs
Info::
robots.txt is present
Got: 7146 bytes
Info::
sitemap.xml is present
Info::
sitemap.xml is valid XML
Info::
sitemap.xml contains 66 entries
Info::
Sitemap index with 66 child sitemaps
Info::
robots.txt references sitemap
robots.txt 200 OK
Size 7146 B Sitemaps referenced 3 User-agents Pinterest, *, adsbot-google, Nutch, AhrefsBot, AhrefsSiteAudit, MJ12bot Blocking No — crawling allowed
# we use Shopify as our ecommerce platform

#  ┏━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┓
#  ┃  Robots & Agent policy                                               ┃
#  ┣━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┫
#  ┃  Checkouts are for humans.                                           ┃
#  ┃  * Automated scraping, “buy-for-me” agents, or any end-to-end flow   ┃
#  ┃    that completes payment without a final human review step is not   ┃
#  ┃    permitted.                                                        ┃
#  ┃  * Legitimate integrators must use the official Checkout Kit:        ┃
#  ┃      https://www.shopify.com/checkout-kit                            ┃
#  ┃                                                                      ┃
#  ┃  Terms of Service: https://www.shopify.com/legal/terms               ┃
#  ┃  Contact: bots@shopify.com                                           ┃
#  ┗━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┛

User-agent: *
Disallow: /a/downloads/-/*
Disallow: /admin
Disallow: /cart
Disallow: /orders
Disallow: /checkouts/
Disallow: /checkout
Disallow: /28528214050/checkouts
Disallow: /28528214050/orders
Disallow: /carts
Disallow: /account
Disallow: /collections/*sort_by*
Disallow: /*/collections/*sort_by*
Disallow: /collections/*+*
Disallow: /collections/*%2B*
Disallow: /collections/*%2b*
Disallow: /*/collections/*+*
Disallow: /*/collections/*%2B*
Disallow: /*/collections/*%2b*
Disallow: */collections/*filter*&*filter*
Disallow: /blogs/*+*
Disallow: /blogs/*%2B*
Disallow: /blogs/*%2b*
Disallow: /*/blogs/*+*
Disallow: /*/blogs/*%2B*
Disallow: /*/blogs/*%2b*
Disallow: /*?*oseid=*
Disallow: /*preview_theme_id*
Disallow: /*preview_script_id*
Disallow: /policies/
Disallow: /*/policies/
Disallow: /*/*?*ls=*&ls=*
Disallow: /*/*?*ls%3D*%3Fls%3D*
Disallow: /*/*?*ls%3d*%3fls%3d*
Disallow: /search
Disallow: /sf_private_access_tokens
Disallow: /apple-app-site-association
Disallow: /.well-known/shopify/monorail
Disallow: /cdn/wpm/*.js
Disallow: /recommendations/products
Disallow: /*/recommendations/products
Disallow: /products/*-[a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9]-remote
Disallow: /*/products/*-[a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9]-remote
Disallow: /collections/*/products/*-[a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9]-remote
Disallow: /*/collections/*/products/*-[a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9]-remote
Sitemap: https://www.harpercollins.com/sitemap.xml

# Google adsbot ignores robots.txt unless specifically named!
User-agent: adsbot-google
Disallow: /checkouts/
Disallow: /checkout
Disallow: /carts
Disallow: /orders
Disallow: /28528214050/checkouts
Disallow: /28528214050/orders
Disallow: /*?*oseid=*
Disallow: /*preview_theme_id*
Disallow: /*preview_script_id*
Disallow: /cdn/wpm/*.js
Disallow: /products/*-[a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9]-remote
Disallow: /*/products/*-[a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9]-remote
Disallow: /collections/*/products/*-[a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9]-remote
Disallow: /*/collections/*/products/*-[a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9]-remote
Disallow: /sf_private_access_tokens

User-agent: Nutch
Disallow: /

User-agent: AhrefsBot
Crawl-delay: 10
Disallow: /a/downloads/-/*
Disallow: /admin
Disallow: /cart
Disallow: /orders
Disallow: /checkouts/
Disallow: /checkout
Disallow: /28528214050/checkouts
Disallow: /28528214050/orders
Disallow: /carts
Disallow: /account
Disallow: /collections/*sort_by*
Disallow: /*/collections/*sort_by*
Disallow: /collections/*+*
Disallow: /collections/*%2B*
Disallow: /collections/*%2b*
Disallow: /*/collections/*+*
Disallow: /*/collections/*%2B*
Disallow: /*/collections/*%2b*
Disallow: */collections/*filter*&*filter*
Disallow: /blogs/*+*
Disallow: /blogs/*%2B*
Disallow: /blogs/*%2b*
Disallow: /*/blogs/*+*
Disallow: /*/blogs/*%2B*
Disallow: /*/blogs/*%2b*
Disallow: /*?*oseid=*
Disallow: /*preview_theme_id*
Disallow: /*preview_script_id*
Disallow: /policies/
Disallow: /*/policies/
Disallow: /*/*?*ls=*&ls=*
Disallow: /*/*?*ls%3D*%3Fls%3D*
Disallow: /*/*?*ls%3d*%3fls%3d*
Disallow: /search
Disallow: /sf_private_access_tokens
Disallow: /apple-app-site-association
Disallow: /.well-known/shopify/monorail
Disallow: /cdn/wpm/*.js
Disallow: /recommendations/products
Disallow: /*/recommendations/products
Disallow: /products/*-[a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9]-remote
Disallow: /*/products/*-[a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9]-remote
Disallow: /collections/*/products/*-[a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9]-remote
Disallow: /*/collections/*/products/*-[a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9]-remote
Sitemap: https://www.harpercollins.com/sitemap.xml

User-agent: AhrefsSiteAudit
Crawl-delay: 10
Disallow: /a/downloads/-/*
Disallow: /admin
Disallow: /cart
Disallow: /orders
Disallow: /checkouts/
Disallow: /checkout
Disallow: /28528214050/checkouts
Disallow: /28528214050/orders
Disallow: /carts
Disallow: /account
Disallow: /collections/*sort_by*
Disallow: /*/collections/*sort_by*
Disallow: /collections/*+*
Disallow: /collections/*%2B*
Disallow: /collections/*%2b*
Disallow: /*/collections/*+*
Disallow: /*/collections/*%2B*
Disallow: /*/collections/*%2b*
Disallow: */collections/*filter*&*filter*
Disallow: /blogs/*+*
Disallow: /blogs/*%2B*
Disallow: /blogs/*%2b*
Disallow: /*/blogs/*+*
Disallow: /*/blogs/*%2B*
Disallow: /*/blogs/*%2b*
Disallow: /*?*oseid=*
Disallow: /*preview_theme_id*
Disallow: /*preview_script_id*
Disallow: /policies/
Disallow: /*/policies/
Disallow: /*/*?*ls=*&ls=*
Disallow: /*/*?*ls%3D*%3Fls%3D*
Disallow: /*/*?*ls%3d*%3fls%3d*
Disallow: /search
Disallow: /sf_private_access_tokens
Disallow: /apple-app-site-association
Disallow: /.well-known/shopify/monorail
Disallow: /cdn/wpm/*.js
Disallow: /recommendations/products
Disallow: /*/recommendations/products
Disallow: /products/*-[a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9]-remote
Disallow: /*/products/*-[a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9]-remote
Disallow: /collections/*/products/*-[a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9]-remote
Disallow: /*/collections/*/products/*-[a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9]-remote
Sitemap: https://www.harpercollins.com/sitemap.xml

User-agent: MJ12bot
Crawl-delay: 10

User-agent: Pinterest
Crawl-delay: 1

sitemap.xml 200 OK
Type Sitemap Index URLs 66 entries Valid XML Yes
Child Sitemaps:
A+
Domain Intelligence
harpercollins.com — via MarkMonitor Inc., 32 years, 5 months old, hosted on Cloudflare
PASS
harpercollins.com — via MarkMonitor Inc., 32 years, 5 months old, hosted on Cloudflare
Info::
Domain registered until Apr 14, 2027 (11 months remaining)
Info::
DNSSEC is not enabled
DNSSEC protects against DNS spoofing attacks. While not required, enabling DNSSEC adds an additional layer of security. Contact your DNS provider to enable it.
Info::
Registrar: MarkMonitor Inc.
Warning::
Registrar lock is NOT enabled
The domain can be transferred without an unlock step. Enable registrar lock (clientTransferProhibited) in your registrar's control panel to protect against unauthorized or accidental transfers.
Info::
Hosting: Cloudflare
Got: AS13335
Domain expiry

269 days

April 14, 2027

SSL certificate

229 days

Issued by DigiCert Inc

Domain age

32 years, 5 months

Registered April 13, 1994

DNSSEC

Not enabled

Protects against DNS spoofing

Hosting

Cloudflare

ASN AS13335

23.227.38.65

Registrar

MarkMonitor Inc.

Unlocked 2 NS records
Expiry timeline
Today
+1 year
Domain expiry SSL expiry Danger zone (≤30 days)
Recommended actions
  • Enable DNSSEC to protect visitors from DNS spoofing
  • Enable registrar lock (clientTransferProhibited) to block unauthorized domain transfers
Registrar MarkMonitor Inc.
Created April 13, 1994 (32 years, 5 months ago)
Expires April 14, 2027 (11 months)
Last Updated March 13, 2026
Name Servers dbru.br.ns.els-gms.att.net, dmtu.mt.ns.els-gms.att.net
DNSSEC Not enabled
Hosting
IP Address 23.227.38.65
ASN AS13335 (CLOUDFLARENET - Cloudflare, Inc., US)
Provider Cloudflare
Data source: rdap (0.2s)

DNSSEC protects against DNS spoofing attacks. While not required, enabling DNSSEC adds an additional layer of security. Contact your DNS provider to enable it.

Why this matters

Without DNSSEC, an attacker who can poison your DNS can hijack your domain — and SSL certs alone don't stop them.

Learn more

DNSSEC adds cryptographic signatures to DNS records, preventing forged responses from poisoning resolver caches. Without it, an attacker who controls the network path can redirect your domain to a malicious server before any HTTPS handshake happens. Most modern registrars (Cloudflare, Google Domains, Route 53) enable it with one toggle.

Source: ICANN / RFC 4033

The domain can be transferred without an unlock step. Enable registrar lock (clientTransferProhibited) in your registrar's control panel to protect against unauthorized or accidental transfers.

Why this matters

Without registrar lock, an attacker who phishes your registrar credentials can transfer the domain in minutes — total brand hijack.

Learn more

Registrar lock (clientTransferProhibited, clientUpdateProhibited, clientDeleteProhibited) requires extra verification before any transfer/update/delete. Every major registrar offers it free. Combined with 2FA on your registrar account, it's the strongest defense against domain hijacking.

Source: ICANN / domain-security best practice

A+
HTTP Probe Timing
Total 142 ms — DNS, TCP, TLS, TTFB, content transfer breakdown
PASS
DNS Lookup DNS Lookup — time to resolve the domain name to an IP address.
11 ms
TCP Connect TCP Connect — time to establish a TCP connection to the server.
2 ms
TLS Handshake TLS Handshake — time to complete the HTTPS encryption handshake.
8 ms
Time to First Byte Time to First Byte — how long the server takes to respond with the first byte of data.
143 ms
Total Time Total request time from DNS lookup through full response.
143 ms

Connection waterfall

DNS Lookup 11 ms TCP Connect 2 ms TLS Handshake 8 ms Server Processing 121 ms Content Transfer 0 ms
A
CDN & Delivery
Cloudflare (DYNAMIC)
PASS
Cloudflare (DYNAMIC)
Info::
Site is served via Cloudflare CDN (edge: SJC)
Got: cf-ray: 9f0018cd8ca931f4-SJC
Info::
CDN cache status: DYNAMIC
CDN Detected: Cloudflare
Provider Cloudflare Cache Status DYNAMIC Evidence cf-ray: 9f0018cd8ca931f4-SJC
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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