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Infrastructure

· 17 checks — DNS, redirects, IPv6, crawlability, URL variants, and domain intelligence rolled into one auditable list.
SCORE
84
GRADE
B
FIX
1
REVIEW
10
PASS
6
INFO
0
Probed from Madrid, Spain
301 Moved Permanently
Checks
17
6 PASS 10 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
DNSSEC
Unsigned (DNSSEC not deployed)
REVIEW
Unsigned (DNSSEC not deployed)
Info::
DNSSEC is not deployed
The zone is not DNSSEC-signed. Users on validating resolvers (Cloudflare 1.1.1.1, Quad9 9.9.9.9, growing default in mobile resolvers) get no protection against DNS spoofing for this domain. Most registrars now offer DNSSEC at a single click; consider enabling it for sites where authenticity matters (banking, healthcare, government).
C
Reverse DNS
Action
0/5 IPs match cert SAN
REVIEW
0/5 IPs match cert SAN
Info::
PTR lookup failed for 20.76.201.171: lookup 20.76.201.171: no such host
No reverse DNS record set for this IP. Common on bare cloud-VM IPs without provider-side PTR; not a security issue.
Info::
PTR lookup failed for 20.112.250.133: lookup 20.112.250.133: no such host
No reverse DNS record set for this IP. Common on bare cloud-VM IPs without provider-side PTR; not a security issue.
Info::
PTR lookup failed for 20.70.246.20: lookup 20.70.246.20: no such host
No reverse DNS record set for this IP. Common on bare cloud-VM IPs without provider-side PTR; not a security issue.
Info::
PTR lookup failed for 20.236.44.162: lookup 20.236.44.162: no such host
No reverse DNS record set for this IP. Common on bare cloud-VM IPs without provider-side PTR; not a security issue.
Info::
PTR lookup failed for 20.231.239.246: lookup 20.231.239.246: no such host
No reverse DNS record set for this IP. Common on bare cloud-VM IPs without provider-side PTR; not a security issue.
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
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 redirects to HTTPS permanently
Got: HTTP 301

www / non-www

200https://www.typescriptlang.org/
200https://typescriptlang.org/

Inconsistent — duplicate content risk

HTTP → HTTPS

301http://typescriptlang.org/ → https://www.typescriptlang.org/

Consistent

B
HTTP Probe Timing
Total 805 ms — DNS, TCP, TLS, TTFB, content transfer breakdown
REVIEW
DNS Lookup DNS Lookup — time to resolve the domain name to an IP address.
23 ms
TCP Connect TCP Connect — time to establish a TCP connection to the server.
159 ms
TLS Handshake TLS Handshake — time to complete the HTTPS encryption handshake.
164 ms
Time to First Byte Time to First Byte — how long the server takes to respond with the first byte of data.
805 ms
Total Time Total request time from DNS lookup through full response.
805 ms

Connection waterfall

DNS Lookup 23 ms TCP Connect 159 ms TLS Handshake 164 ms Server Processing 460 ms Content Transfer 0 ms
B
TLS Certificate Expiry & Recommendations
72 days until leaf cert expires — 4 issues to address
REVIEW

Certificate validity

72
days left
0d 30d 60d 90d+

Recommended actions

  • 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
B
CDN Cache Observability
No CDN cache-status headers in the response
REVIEW
No CDN cache-status headers in the response
Info::
No CDN cache-status headers in the response
Without an X-Cache / CF-Cache-Status / X-Vercel-Cache / Age header, you can't tell from outside whether a request hit the cache or went to origin. Operationally important: enables debugging stale-content reports and verifying cache rules. Most managed CDN platforms emit at least one of these by default; absence often means the platform's diagnostic headers are stripped at an upstream proxy.
B
Operational Status Page
No status page link detected
REVIEW
No status page link detected
Info::
No operational status page link detected
Status pages communicate planned maintenance and incidents to users -- a hallmark of operationally-mature services. Most SaaS teams publish one via Atlassian Statuspage, Instatus, BetterUptime, or a self-hosted Cachet. Smaller sites legitimately don't need one; flagged as Info, not a failure.
B
Health Check Endpoint
No conventional health endpoint found
REVIEW
No conventional health endpoint found
Info::
No conventional health endpoint found
Health endpoints (/health, /healthz, /status, /ping, /api/health) let uptime monitors, load balancers, and orchestration systems (Kubernetes, ECS, Fly.io) verify the service is alive. Marketing sites and small services often skip them legitimately; flagged as Info, not a failure. Probe results: /api/health: 404, /health: 404, /healthz: 404, /ping: 404, /status: 404.
A+
DNS Records
5 A records, 33 ms lookup
PASS
5 A records, 33 ms lookup
Info::
Resolves to 5 IPv4 address(es)
Got: 20.76.201.171, 20.112.250.133, 20.70.246.20, 20.236.44.162, 20.231.239.246
Info::
No IPv6 (AAAA) records
Info::
4 nameserver(s) configured
Got: ns4-04.azure-dns.info, ns2-04.azure-dns.net, ns1-04.azure-dns.com, ns3-04.azure-dns.org
Info::
No MX records — email not configured via DNS
Info::
No SPF record found in TXT records
SPF helps prevent email spoofing. Add a TXT record starting with 'v=spf1'.
Info::
DNS resolution time: 33 ms
Got: 33 ms
A20.76.201.171, 20.112.250.133, 20.70.246.20, 20.236.44.162, 20.231.239.246
AAAA—
CNAME—
NSns4-04.azure-dns.info, ns2-04.azure-dns.net, ns1-04.azure-dns.com, ns3-04.azure-dns.org
MX—
TXT
chq4pfvlfb4v94bl6lfmlg4rt8mzcy6s
71z7qrm0ktfz0fjzj9mxyf5ntv9fydsm
CAALookup not available with standard resolver
Resolved in 33 ms

SPF helps prevent email spoofing. Add a TXT record starting with 'v=spf1'.

Why this matters

Without SPF, receiving servers can't validate sending IPs — your domain is easier to spoof in phishing.

Learn more ▾

SPF complements DMARC. Both should be published. SPF records list authorized sending IPs (e.g., `v=spf1 include:_spf.google.com ~all` for Google Workspace). After publishing, verify in Google Postmaster Tools or mxtoolbox.

Source: RFC 7208 (SPF)

A+
Subdomain Takeover
No subdomain takeover risk detected
PASS
No subdomain takeover risk detected
Info::
No CNAME record present
A
CAA Records
CAA records present
PASS
CAA records present
Info::
No CAA iodef tag — won't be notified of failed issuance attempts
Add `0 iodef "mailto:security@example.com"` to receive notifications when a CA refuses issuance because it doesn't match your CAA policy. Useful signal for detecting issuance attempts by unauthorized CAs.
A+
Multi-Resolver DNS Speed
Mean 19ms across 3 resolvers (spread 1ms)
PASS
Mean 19ms across 3 resolvers (spread 1ms)
Info::
Quad9: 20ms
Got: 20ms via 9.9.9.9:53
Info::
Cloudflare: 19ms
Got: 19ms via 1.1.1.1:53
Info::
Google: 20ms
Got: 20ms via 8.8.8.8:53
A
Redirect Chain
1 redirect(s), 851 ms total
PASS
1 redirect(s), 851 ms total
Info::
Single redirect
Got: https://typescriptlang.org → https://www.typescriptlang.org/ (301)
Info::
WWW normalization redirect
Info::
Redirect overhead: 851 ms total
Got: 851 ms

https://typescriptlang.org

844 ms · HTTP/1.1

301

https://www.typescriptlang.org/

7 ms · HTTP/1.1 FINAL

#URLStatusTimeProtocolServer
1https://typescriptlang.org301844 msHTTP/1.1Kestrel
2https://www.typescriptlang.org/2007 msHTTP/1.1GitHub.com

See the visual redirect chain in the HTTP Probe tab →

A+
Domain Intelligence
typescriptlang.org — via MarkMonitor Inc., 14 years, 2 months old, hosted on Microsoft Azure
PASS
typescriptlang.org — via MarkMonitor Inc., 14 years, 2 months old, hosted on Microsoft Azure
Info::
Domain registered until Aug 13, 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: Microsoft Azure
Got: AS8075
Domain expiry

352 days

August 13, 2027

SSL certificate

72 days

Issued by Microsoft Corporation

Domain age

14 years, 2 months

Registered August 13, 2012

DNSSEC

Not enabled

Protects against DNS spoofing

Hosting

Microsoft Azure

ASN AS8075

20.76.201.171

Registrar

MarkMonitor 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 MarkMonitor Inc.
Created August 13, 2012 (14 years, 2 months ago)
Expires August 13, 2027 (11 months)
Last Updated August 11, 2026
Name Servers ns3-04.azure-dns.org, ns1-04.azure-dns.com, ns2-04.azure-dns.net, ns4-04.azure-dns.info
DNSSEC Not enabled
Hosting
IP Address 20.76.201.171
ASN AS8075 (MICROSOFT-CORP-MSN-AS-BLOCK - Microsoft Corporation, US)
Provider Microsoft Azure
Data source: rdap (0.8s)

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

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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