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https://flippingbook.com

Infrastructure

· 9 checks — DNS, redirects, IPv6, crawlability, URL variants, and domain intelligence rolled into one auditable list.
SCORE
92
GRADE
A
FIX
1
REVIEW
2
PASS
6
INFO
0
Probed from Madrid, Spain
200 OK
Checks
9
6 PASS 2 REVIEW 1 FIX
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
74 days until leaf cert expires — 3 issues to address
REVIEW

Certificate validity

74
days left
0d 30d 60d 90d+

Recommended actions

  • Submit your domain to hstspreload.org to be added to the Chrome preload list
  • 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, 35 ms lookup
PASS
1 A records, 35 ms lookup
Info::
Resolves to 1 IPv4 address(es)
Got: 3.86.120.57
Info::
Single A record — no DNS redundancy
Multiple A records provide failover if one server goes down.
Info::
No IPv6 (AAAA) records
Info::
4 nameserver(s) configured
Got: ns-996.awsdns-60.net, ns-1554.awsdns-02.co.uk, ns-1245.awsdns-27.org, ns-264.awsdns-33.com
Info::
6 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: 35 ms
Got: 35 ms
A3.86.120.57
AAAA—
CNAME—
NSns-996.awsdns-60.net, ns-1554.awsdns-02.co.uk, ns-1245.awsdns-27.org, ns-264.awsdns-33.com
MX
1 aspmx.l.google.com
5 alt2.aspmx.l.google.com
5 alt1.aspmx.l.google.com
10 alt4.aspmx.l.google.com
10 alt3.aspmx.l.google.com
20 mail-out.flippingbook.com
TXT
SPF v=spf1 mx ip4:44.197.27.142 include:mail.zendesk.com include:spf.mandrillapp.com...
google-site-verification=_Yf3cG13GgmuQTujaypgUIlKMSSaqFlg88eczSe1MwM
google-site-verification=tauqtG7_w_McWkWnHf4w62Sp8NJ3lfYH5EL7RicYhkk
google-site-verification=NGt6Oetv-U6GAt2RRFcf6yIob260IHdAgtj6_lrLMbQ
google-site-verification=FkFYeZcM8QumJcJ4zh1IREZcT4ERjnYPJqaBw-ayrMQ
google-site-verification=j9JMUKYFUy_wowDxn7dNu1g-dtP0nFTawdO3MA4gzWA
apple-domain-verification=0DaNALzfZVtlsDLu
pinterest-site-verification=2471a85c9d1fa993736b484575c698c0
CAALookup not available with standard resolver
Resolved in 35 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
No redirects — direct access
PASS
No redirects — direct access
Info::
No redirects — direct access
Got: https://flippingbook.com

https://flippingbook.com

402 ms · HTTP/1.1 FINAL

#URLStatusTimeProtocolServer
1https://flippingbook.com200402 msHTTP/1.1nginx
A+
Crawlability
robots.txt present, sitemap with 2 URLs
PASS
robots.txt present, sitemap with 2 URLs
Info::
robots.txt is present
Got: 1842 bytes
Info::
sitemap.xml is present
Info::
sitemap.xml is valid XML
Info::
sitemap.xml contains 2 entries
Info::
Sitemap index with 2 child sitemaps
Info::
robots.txt references sitemap
robots.txt 200 OK
Size 1842 B Sitemaps referenced 1 User-agents Yandex, Googlebot, * Blocking No — crawling allowed
User-agent: Yandex

Allow: /

Allow: /account/online/new

Disallow: /ru/

Disallow: /downloads/*/

Disallow: /thank-you/

Disallow: /user-guide/

Disallow: /quick-start/

Disallow: /help/quick-start/

Disallow: /files/

Disallow: /*q=

Disallow: /.swf

Disallow: /view/

Disallow: /externallogin

Disallow: /logout

Disallow: /account

Disallow: /account/

Disallow: /deprecated-browser

Disallow: /book-demo

Disallow: /downloads/flippingbook-app

Disallow: /shift-content-add-pages-calculator/

Disallow: /shift-content-delete-pages-calculator/

Disallow: /shift-content-move-pages-calculator/


User-agent: Googlebot

Allow: /

Allow: /account/online/new

Disallow: /ru/

Disallow: /downloads/*/

Disallow: /thank-you/

Disallow: /user-guide/

Disallow: /quick-start/

Disallow: /help/quick-start/

Disallow: /files/

Disallow: /*q=

Disallow: /.swf

Disallow: /view/

Disallow: /externallogin

Disallow: /logout

Disallow: /account

Disallow: /account/

Disallow: /deprecated-browser

Disallow: /book-demo

Disallow: /downloads/flippingbook-app

Disallow: /shift-content-add-pages-calculator/

Disallow: /shift-content-delete-pages-calculator/

Disallow: /shift-content-move-pages-calculator/


User-Agent: *

Allow: /

Allow: /account/online/new

Disallow: /ru/

Disallow: /downloads/*/

Disallow: /thank-you/

Disallow: /user-guide/

Disallow: /quick-start/

Disallow: /help/quick-start/

Disallow: /files/

Disallow: /*q=

Disallow: /.swf

Disallow: /view/

Disallow: /externallogin

Disallow: /logout

Disallow: /account

Disallow: /account/

Disallow: /deprecated-browser

Disallow: /book-demo

Disallow: /downloads/flippingbook-app

Disallow: /shift-content-add-pages-calculator/

Disallow: /shift-content-delete-pages-calculator/

Disallow: /shift-content-move-pages-calculator/


Sitemap: https://flippingbook.com/sitemap.xml
sitemap.xml 200 OK
Type Sitemap Index URLs 2 entries Valid XML Yes
Child Sitemaps:
A+
URL Variants
www/non-www, trailing slash, HTTP→HTTPS
PASS
www/non-www, trailing slash, HTTP→HTTPS
Info::
www/non-www redirect configured correctly (preferred: non-www)
Info::
HTTP correctly 301-redirects to HTTPS

www / non-www

301https://www.flippingbook.com/
200https://flippingbook.com/

Preferred variant: non-www

HTTP → HTTPS

301http://flippingbook.com/ → https://flippingbook.com/

Consistent

A+
Domain Intelligence
flippingbook.com — via Amazon Registrar, Inc., 21 years, 9 months old, hosted on AWS
PASS
flippingbook.com — via Amazon Registrar, Inc., 21 years, 9 months old, hosted on AWS
Info::
Domain registered until Oct 19, 2026 (6 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: Amazon Registrar, 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: AWS
Got: AS16509
Domain expiry

125 days

October 19, 2026

SSL certificate

74 days

Issued by Let's Encrypt

Domain age

21 years, 9 months

Registered October 19, 2004

DNSSEC

Not enabled

Protects against DNS spoofing

Hosting

AWS

ASN AS16509

3.86.120.57

Registrar

Amazon Registrar, Inc.

Unlocked 4 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 Amazon Registrar, Inc.
Created October 19, 2004 (21 years, 9 months ago)
Expires October 19, 2026 (6 months)
Last Updated September 14, 2025
Name Servers ns-1245.awsdns-27.org, ns-1554.awsdns-02.co.uk, ns-264.awsdns-33.com, ns-996.awsdns-60.net
DNSSEC Not enabled
Hosting
IP Address 3.86.120.57
ASN AS16509 (AMAZON-02 - Amazon.com, Inc., US)
Provider AWS
Data source: rdap (0.3s)

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 725 ms — DNS, TCP, TLS, TTFB, content transfer breakdown
PASS
DNS Lookup DNS Lookup — time to resolve the domain name to an IP address.
28 ms
TCP Connect TCP Connect — time to establish a TCP connection to the server.
99 ms
TLS Handshake TLS Handshake — time to complete the HTTPS encryption handshake.
100 ms
Time to First Byte Time to First Byte — how long the server takes to respond with the first byte of data.
423 ms
Total Time Total request time from DNS lookup through full response.
726 ms

Connection waterfall

DNS Lookup 28 ms TCP Connect 99 ms TLS Handshake 100 ms Server Processing 197 ms Content Transfer 302 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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