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Infrastructure

· 9 checks — DNS, redirects, IPv6, crawlability, URL variants, and domain intelligence rolled into one auditable list.
SCORE
85
GRADE
B
FIX
0
REVIEW
4
PASS
5
INFO
0
Probed from Madrid, Spain
301 Moved Permanently
Checks
9
5 PASS 4 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

C
Crawlability
Action
robots.txt present, sitemap with 0 URLs
REVIEW
robots.txt present, sitemap with 0 URLs
Info::
robots.txt is present
Got: 10240 bytes
Info::
sitemap.xml is present
Warning::
sitemap.xml contains invalid XML
Search engines may not be able to parse the sitemap. Fix XML validation errors.
Warning::
sitemap.xml is empty — no URLs found
An empty sitemap provides no value. Add <url> entries for your pages.
Info::
robots.txt does not reference a sitemap
Add a 'Sitemap:' directive to robots.txt so search engines can discover your sitemap.

Search engines may not be able to parse the sitemap. Fix XML validation errors.

Why this matters

An unparseable sitemap is silently ignored by Google — the URLs it advertises are never queued for crawl.

Learn more ▾

Google's sitemap parser is strict about XML validity. A single unescaped `&` or unclosed tag invalidates the whole file. Run your sitemap through a validator (Search Console's Sitemaps report flags it) and fix the offending entry. Most generators escape correctly; mistakes usually come from manually-written entries.

Source: sitemaps.org / Google Search Central

An empty sitemap provides no value. Add <url> entries for your pages.

Why this matters

An empty sitemap signals 'no content to index' to Google — actively harmful versus having no sitemap at all.

Learn more ▾

Google compares URLs in the sitemap against URLs it has crawled. An empty sitemap on a site with thousands of pages signals abandonment. Either populate it correctly (most CMSes auto-generate) or delete the file and let Google crawl normally.

Source: Google Search Central / sitemaps.org

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 10240 B Sitemaps referenced 0 User-agents Blocking No — crawling allowed







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sitemap.xml 200 OK
Type URL Set URLs 0 entries Valid XML No
B
TLS Certificate Expiry & Recommendations
43 days until leaf cert expires — 4 issues to address
REVIEW

Certificate validity

43
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
B
CDN & Delivery
Cloudflare
REVIEW
Cloudflare
Info::
Site is served via Cloudflare CDN (edge: CDG)
Got: cf-ray: 9f0859ea485a7e9b-CDG
CDN Detected: Cloudflare
Provider Cloudflare Evidence cf-ray: 9f0859ea485a7e9b-CDG
A+
DNS Records
2 A records, 47 ms lookup
PASS
2 A records, 47 ms lookup
Info::
Resolves to 2 IPv4 address(es)
Got: 104.17.99.190, 104.17.98.190
Info::
No IPv6 (AAAA) records
Info::
2 nameserver(s) configured
Got: george.ns.cloudflare.com, lara.ns.cloudflare.com
Info::
No MX records — email not configured via DNS
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: 47 ms
Got: 47 ms
A104.17.99.190, 104.17.98.190
AAAA—
CNAME—
NSgeorge.ns.cloudflare.com, lara.ns.cloudflare.com
MX—
TXT
SPF v=spf1 -all
CAALookup not available with standard resolver
Resolved in 47 ms

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), 687 ms total
PASS
1 redirect(s), 687 ms total
Info::
Single redirect
Got: https://sizzlejs.com → https://github.com/jquery/sizzle/wiki (301)
Info::
Redirect overhead: 687 ms total
Got: 687 ms
Info::
Cross-domain redirect detected

https://sizzlejs.com

78 ms · HTTP/1.1

301

https://github.com/jquery/sizzle/wiki

609 ms · HTTP/1.1 FINAL

#URLStatusTimeProtocolServer
1https://sizzlejs.com30178 msHTTP/1.1cloudflare
2https://github.com/jquery/sizzle/wiki200609 msHTTP/1.1github.com

See the visual redirect chain in the HTTP Probe tab →

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.sizzlejs.com/
200https://sizzlejs.com/

Preferred variant: non-www

HTTP → HTTPS

301http://sizzlejs.com/ → https://github.com/jquery/sizzle/wiki

Consistent

A+
Domain Intelligence
sizzlejs.com — via 1API GmbH, 17 years, 7 months old, hosted on Cloudflare
PASS
sizzlejs.com — via 1API GmbH, 17 years, 7 months old, hosted on Cloudflare
Info::
Domain registered until Dec 3, 2026 (7 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: 1API GmbH
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

142 days

December 3, 2026

SSL certificate

43 days

Issued by Google Trust Services

Domain age

17 years, 7 months

Registered December 3, 2008

DNSSEC

Not enabled

Protects against DNS spoofing

Hosting

Cloudflare

ASN AS13335

104.17.98.190

Registrar

1API GmbH

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 1API GmbH
Created December 3, 2008 (17 years, 7 months ago)
Expires December 3, 2026 (7 months)
Last Updated November 28, 2025
Name Servers george.ns.cloudflare.com, lara.ns.cloudflare.com
DNSSEC Not enabled
Hosting
IP Address 104.17.98.190
ASN AS13335 (CLOUDFLARENET - Cloudflare, Inc., US)
Provider Cloudflare
Data source: rdap (0.4s)

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

Connection waterfall

DNS Lookup 50 ms TCP Connect 17 ms TLS Handshake 39 ms Server Processing 20 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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