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Infrastructure

· 9 checks — DNS, redirects, IPv6, crawlability, URL variants, and domain intelligence rolled into one auditable list.
SCORE
88
GRADE
B
FIX
0
REVIEW
2
PASS
7
INFO
0
Probed from Singapore, Singapore
301 Moved Permanently
Checks
9
7 PASS 2 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

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

Certificate validity

340
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
4 A records, 87 ms lookup
PASS
4 A records, 87 ms lookup
Info::
Resolves to 4 IPv4 address(es)
Got: 13.35.238.48, 13.35.238.26, 13.35.238.39, 13.35.238.29
Info::
No IPv6 (AAAA) records
Warning::
CNAME record at zone apex
A CNAME at the zone apex can break MX and NS records. Use ALIAS/ANAME or A records instead.
Got: d2p9kan0nxscnn.cloudfront.net
Info::
4 nameserver(s) configured
Got: ns-1179.awsdns-19.org, ns-1544.awsdns-01.co.uk, ns-457.awsdns-57.com, ns-971.awsdns-57.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::
No SPF record found in TXT records
SPF helps prevent email spoofing. Add a TXT record starting with 'v=spf1'.
Info::
DNS resolution time: 87 ms
Got: 87 ms
A13.35.238.48, 13.35.238.26, 13.35.238.39, 13.35.238.29
AAAA
CNAMEd2p9kan0nxscnn.cloudfront.net
NSns-1179.awsdns-19.org, ns-1544.awsdns-01.co.uk, ns-457.awsdns-57.com, ns-971.awsdns-57.net
MX
TXT
CAALookup not available with standard resolver
Resolved in 87 ms

A CNAME at the zone apex can break MX and NS records. Use ALIAS/ANAME or A records instead.

Why this matters

CNAME at the apex (example.com) breaks every other apex record (MX, TXT, NS) — DNS-protocol violation per RFC 1034.

Learn more

RFC 1034 forbids CNAME alongside other records at the same name. Some DNS providers offer ALIAS / ANAME / flattened-CNAME records that work around this — use those instead. Otherwise apex-level CNAME breaks email (no MX), domain ownership verification (no TXT), and more.

Source: RFC 1034

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)

A
Redirect Chain
1 redirect(s), 38 ms total
PASS
1 redirect(s), 38 ms total
Info::
Single redirect
Got: https://www.twilio.com → https://www.twilio.com/en-us (301)

https://www.twilio.com

20 ms · HTTP/1.1

301

https://www.twilio.com/en-us

18 ms · HTTP/1.1 FINAL

#URLStatusTimeProtocolServer
1https://www.twilio.com30120 msHTTP/1.1
2https://www.twilio.com/en-us20018 msHTTP/1.1

See the visual redirect chain in the HTTP Probe tab →

A+
Crawlability
robots.txt present, sitemap with 7 URLs
PASS
robots.txt present, sitemap with 7 URLs
Info::
robots.txt is present
Got: 892 bytes
Info::
sitemap.xml is present
Info::
sitemap.xml is valid XML
Info::
sitemap.xml contains 7 entries
Info::
Sitemap index with 7 child sitemaps
Info::
robots.txt does not reference a sitemap
Add a 'Sitemap:' directive to robots.txt so search engines can discover your sitemap.

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 892 B Sitemaps referenced 0 User-agents *, Swiftbot Blocking No — crawling allowed
User-agent: *

Disallow: /resources/
Disallow: /azure
Disallow: /search
Disallow: /help/search

# 'Allow' - nonstandard REP Directive
Allow: /docs/libraries/reference/twilio-php/index.html
Allow: /docs/libraries/reference/twilio-node/index.html
Allow: /docs/libraries/reference/twilio-java/index.html
Allow: /docs/libraries/reference/twilio-ruby/index.html
Allow: /docs/libraries/reference/twilio-python/index.html
Allow: /docs/libraries/reference/twilio-csharp/index.html

Disallow: /docs/libraries/reference/twilio-php/
Disallow: /docs/libraries/reference/twilio-node/
Disallow: /docs/libraries/reference/twilio-java/
Disallow: /docs/libraries/reference/twilio-ruby/
Disallow: /docs/libraries/reference/twilio-python/
Disallow: /docs/libraries/reference/twilio-csharp/
Disallow: /docs/admin/
Disallow: /en-us/test
Disallow: /en-us/personalized-solutions

User-agent: Swiftbot
Crawl-delay: 1
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: www)
Info::
HTTP correctly 301-redirects to HTTPS

www / non-www

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

Preferred variant: www

HTTP → HTTPS

301http://www.twilio.com/ https://www.twilio.com/

Consistent

A+
Domain Intelligence
twilio.com — via MarkMonitor Inc., 18 years, 8 months old, hosted on AWS
PASS
twilio.com — via MarkMonitor Inc., 18 years, 8 months old, hosted on AWS
Info::
Domain registered until Oct 26, 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: MarkMonitor Inc.
Info::
Hosting: AWS
Got: AS14618
Domain expiry

133 days

October 26, 2026

SSL certificate

340 days

Issued by Amazon

Domain age

18 years, 8 months

Registered October 26, 2007

DNSSEC

Not enabled

Protects against DNS spoofing

Hosting

AWS

ASN AS14618

44.199.52.48

Registrar

MarkMonitor Inc.

Lock status unknown 6 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 MarkMonitor Inc.
Created October 26, 2007 (18 years, 8 months ago)
Expires October 26, 2026 (6 months)
Last Updated September 24, 2024
Name Servers a1-83.akam.net, a11-64.akam.net, a24-65.akam.net, ns0.dnsmadeeasy.com, ns1.dnsmadeeasy.com, ns2.dnsmadeeasy.com
DNSSEC Not enabled
Hosting
IP Address 44.199.52.48
ASN AS14618 (AMAZON-AES - Amazon.com, Inc., US)
Provider AWS
Data source: rdap (0.7s)

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+
HTTP Probe Timing
Total 31 ms — DNS, TCP, TLS, TTFB, content transfer breakdown
PASS
DNS Lookup DNS Lookup — time to resolve the domain name to an IP address.
7 ms
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.
4 ms
Time to First Byte Time to First Byte — how long the server takes to respond with the first byte of data.
31 ms
Total Time Total request time from DNS lookup through full response.
31 ms

Connection waterfall

DNS Lookup 7 ms TCP Connect 1 ms TLS Handshake 4 ms Server Processing 18 ms Content Transfer 0 ms
A
CDN & Delivery
AWS CloudFront (Miss from cloudfront)
PASS
AWS CloudFront (Miss from cloudfront)
Info::
Site is served via AWS CloudFront CDN (edge: SIN2-P8)
Got: x-amz-cf-id: s4tG8OwN3esTNkRW__N7Vv5NgNx092gpNBpEBTZH_LQ-E5Q-Yya0Lw==
Info::
CDN cache status: Miss from cloudfront
CDN Detected: AWS CloudFront
Provider AWS CloudFront Cache Status Miss from cloudfront Evidence x-amz-cf-id: s4tG8OwN3esTNkRW__N7Vv5NgNx092gpNBpEBTZH_LQ-E5Q-Yya0Lw==
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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