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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
1
REVIEW
3
PASS
5
INFO
0
Probed from Singapore, Singapore
200 OK
Checks
9
5 PASS 3 REVIEW 1 FIX
F
HTTP Probe Timing
Action
Total 5078 ms — DNS, TCP, TLS, TTFB, content transfer breakdown
FIX
DNS Lookup DNS Lookup — time to resolve the domain name to an IP address.
5.05 s
TCP Connect TCP Connect — time to establish a TCP connection to the server.
1 ms
TLS Handshake TLS Handshake — time to complete the HTTPS encryption handshake.
7 ms
Time to First Byte Time to First Byte — how long the server takes to respond with the first byte of data.
5.08 s
Total Time Total request time from DNS lookup through full response.
5.08 s

Connection waterfall

DNS Lookup 5.05 s TCP Connect 1 ms TLS Handshake 7 ms Server Processing 13 ms Content Transfer 4 ms
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
robots.txt present, no sitemap
REVIEW
robots.txt present, no sitemap
Info::
robots.txt is present
Got: 24 bytes
Info::
No sitemap.xml found
A sitemap helps search engines discover and index your pages more efficiently.
Info::
robots.txt does not reference a sitemap
Add a 'Sitemap:' directive to robots.txt so search engines can discover your sitemap.

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

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 24 B Sitemaps referenced 0 User-agents * Blocking No — crawling allowed
User-agent: *
Disallow:
sitemap.xml No sitemap found

No sitemap found

Adding a sitemap helps search engines discover your pages.

B
TLS Certificate Expiry & Recommendations
39 days until leaf cert expires — 4 issues to address
REVIEW

Certificate validity

39
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
A
DNS Records
2 A records, 5114 ms lookup
PASS
2 A records, 5114 ms lookup
Info::
Resolves to 2 IPv4 address(es)
Got: 66.33.60.130, 76.76.21.61
Info::
No IPv6 (AAAA) records
Info::
2 nameserver(s) configured
Got: edna.ns.cloudflare.com, norm.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::
No SPF record found in TXT records
SPF helps prevent email spoofing. Add a TXT record starting with 'v=spf1'.
Warning::
DNS resolution is slow (5114 ms)
Slow DNS adds latency to every page load. Consider a faster DNS provider.
Got: 5114 ms
A66.33.60.130, 76.76.21.61
AAAA—
CNAME—
NSedna.ns.cloudflare.com, norm.ns.cloudflare.com
MX—
TXT
google-site-verification=a5RC7LuUuYSWBrPBwybnA2bPZSh4aYEDbYEg7O4t9l4
CAALookup not available with standard resolver
Resolved in 5114 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.

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)

Slow DNS adds latency to every page load. Consider a faster DNS provider.

Why this matters

DNS resolution is slow — anycast DNS providers (Cloudflare, Route 53) typically resolve <50ms globally.

Source: DNS performance benchmarks

A+
Redirect Chain
No redirects — direct access
PASS
No redirects — direct access
Info::
No redirects — direct access
Got: https://react.dev

https://react.dev

66 ms · HTTP/1.1 FINAL

#URLStatusTimeProtocolServer
1https://react.dev20066 msHTTP/1.1Vercel
A
URL Variants
www/non-www, trailing slash, HTTP→HTTPS
PASS
www/non-www, trailing slash, HTTP→HTTPS
Warning::
HTTP→HTTPS redirect uses 302 instead of 301
Got: 302 temporary redirect Expected: 301 permanent redirect

www / non-www

308https://www.react.dev/
200https://react.dev/

HTTP → HTTPS

308http://react.dev/ → https://react.dev/

Use 301 (permanent) instead of 302 (temporary)

A+
Domain Intelligence
react.dev — via RegistrarSEC, LLC, 7 years, 2 months old, hosted on AWS
PASS
react.dev — via RegistrarSEC, LLC, 7 years, 2 months old, hosted on AWS
Info::
Domain registered until Feb 19, 2027 (10 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: RegistrarSEC, LLC
Info::
Hosting: AWS
Got: AS16509
Domain expiry

223 days

February 19, 2027

SSL certificate

39 days

Issued by Let's Encrypt

Domain age

7 years, 2 months

Registered February 19, 2019

DNSSEC

Not enabled

Protects against DNS spoofing

Hosting

AWS

ASN AS16509

66.33.60.130

Registrar

RegistrarSEC, LLC

Lock status unknown 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
Registrar RegistrarSEC, LLC
Created February 19, 2019 (7 years, 2 months ago)
Expires February 19, 2027 (10 months)
Last Updated November 27, 2025
Name Servers edna.ns.cloudflare.com, norm.ns.cloudflare.com
DNSSEC Not enabled
Hosting
IP Address 66.33.60.130
ASN AS16509 (AMAZON-02 - Amazon.com, Inc., US)
Provider AWS
Data source: rdap (8.5s)

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

A+
CDN & Delivery
Vercel (HIT)
PASS
Vercel (HIT)
Info::
Site is served via Vercel CDN
Got: x-vercel-id: sin1::gjfqb-1775320978201-35b636158430
Info::
CDN cache status: HIT
CDN Detected: Vercel
Provider Vercel Cache Status HIT Evidence x-vercel-id: sin1::gjfqb-1775320978201-35b636158430
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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