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https://a.co

Infrastructure

· 9 checks — DNS, redirects, IPv6, crawlability, URL variants, and domain intelligence rolled into one auditable list.
SCORE
84
GRADE
B
FIX
1
REVIEW
4
PASS
4
INFO
0
Probed from Madrid, Spain
302 Found
Checks
9
4 PASS 4 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.

B
Redirect Chain
2 redirect(s), 363 ms total
REVIEW
2 redirect(s), 363 ms total
Warning::
2 redirects before reaching final URL
Each redirect adds latency. Try to minimize the chain to 1 hop.
Info::
HTTP to HTTPS redirect present
Info::
WWW normalization redirect
Warning::
2-hop chain could be reduced to 1 hop
Redirect directly from https://a.co to https://www.amazon.com/
Info::
Uses 302 (temporary) redirect
If permanent, use 301 instead.
Got: https://a.co
Info::
Cross-domain redirect detected

https://a.co

318 ms · HTTP/1.1

302

http://www.amazon.com/

36 ms · HTTP/1.1

301

https://www.amazon.com/

10 ms · HTTP/1.1 FINAL

#URLStatusTimeProtocolServer
1https://a.co302318 msHTTP/1.1Server
2http://www.amazon.com/30136 msHTTP/1.1CloudFront
3https://www.amazon.com/20210 msHTTP/1.1CloudFront

See the visual redirect chain in the HTTP Probe tab →

Each redirect adds latency. Try to minimize the chain to 1 hop.

Why this matters

Redirect chain — each hop adds latency; combine into one redirect where possible.

Source: Google Search Central / web.dev

Redirect directly from https://a.co to https://www.amazon.com/

Why this matters

Redirect chain could be flattened to one hop — server config tweak removes intermediate latency.

Source: web.dev

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

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
Crawlability
no robots.txt, no sitemap
REVIEW
no robots.txt, no sitemap
Info::
No robots.txt found
robots.txt is optional but recommended. It tells search engine crawlers which pages to index.
Info::
No sitemap.xml found
A sitemap helps search engines discover and index your pages more efficiently.

robots.txt is optional but recommended. It tells search engine crawlers which pages to index.

Why this matters

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.

Why this matters

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

robots.txt No robots.txt found

No robots.txt found

This is fine for most sites — a missing robots.txt allows all crawling by default.

sitemap.xml No sitemap found

No sitemap found

Adding a sitemap helps search engines discover your pages.

B
TLS Certificate Expiry & Recommendations
119 days until leaf cert expires — 3 issues to address
REVIEW

Certificate validity

119
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
3 A records, 27 ms lookup
PASS
3 A records, 27 ms lookup
Info::
Resolves to 3 IPv4 address(es)
Got: 98.87.170.202, 98.87.170.8, 44.215.138.88
Info::
No IPv6 (AAAA) records
Info::
6 nameserver(s) configured
Got: pdns6.ultradns.co.uk, pdns5.ultradns.info, pdns3.ultradns.org, pdns4.ultradns.org, pdns2.ultradns.net, pdns1.ultradns.net
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: 27 ms
Got: 27 ms
A98.87.170.202, 98.87.170.8, 44.215.138.88
AAAA
CNAME
NSpdns6.ultradns.co.uk, pdns5.ultradns.info, pdns3.ultradns.org, pdns4.ultradns.org, pdns2.ultradns.net, pdns1.ultradns.net
MX
TXT
SPF v=spf1 -all
CAALookup not available with standard resolver
Resolved in 27 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+
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.a.co/
200https://a.co/

Preferred variant: non-www

HTTP → HTTPS

301http://a.co/ https://a.co/

Consistent

A+
Domain Intelligence
a.co — via MarkMonitor, Inc., 16 years, 2 months old, hosted on AWS
PASS
a.co — via MarkMonitor, Inc., 16 years, 2 months old, hosted on AWS
Info::
Domain registered until Apr 25, 2027 (1 years remaining)
Info::
Registrar: MarkMonitor, Inc.
Info::
Registrar lock is enabled
Domain cannot be transferred without explicit unlock from the registrar. This protects against unauthorized transfers.
Info::
Hosting: AWS
Got: AS14618
Domain expiry

284 days

April 25, 2027

SSL certificate

119 days

Issued by Amazon

Domain age

16 years, 2 months

Registered April 26, 2010

DNSSEC

Status unknown

Protects against DNS spoofing

Hosting

AWS

ASN AS14618

98.87.170.202

Registrar

MarkMonitor, Inc.

Locked 6 NS records
Expiry timeline
Today
+1 year
Domain expiry SSL expiry Danger zone (≤30 days)
Registrar MarkMonitor, Inc.
Created April 26, 2010 (16 years, 2 months ago)
Expires April 25, 2027 (1 years)
Last Updated February 5, 2026
Name Servers pdns3.ultradns.org, pdns4.ultradns.org, pdns2.ultradns.net, pdns1.ultradns.net, pdns5.ultradns.info, pdns6.ultradns.co.uk
Registrant Amazon Technologies, Inc.
Hosting
IP Address 98.87.170.202
ASN AS14618 (AMAZON-AES - Amazon.com, Inc., US)
Provider AWS
Data source: whois (1.5s)

Domain cannot be transferred without explicit unlock from the registrar. This protects against unauthorized transfers.

Why this matters

Registrar lock (clientTransferProhibited et al.) prevents unauthorized domain transfers — strongest defense against domain hijacking.

Source: ICANN / domain-security best practice

A+
HTTP Probe Timing
Total 324 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.
97 ms
TLS Handshake TLS Handshake — time to complete the HTTPS encryption handshake.
101 ms
Time to First Byte Time to First Byte — how long the server takes to respond with the first byte of data.
325 ms
Total Time Total request time from DNS lookup through full response.
325 ms

Connection waterfall

DNS Lookup 27 ms TCP Connect 97 ms TLS Handshake 101 ms Server Processing 100 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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