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https://ons.gov.uk

Infrastructure

· 9 checks — DNS, redirects, IPv6, crawlability, URL variants, and domain intelligence rolled into one auditable list.
SCORE
82
GRADE
B
FIX
1
REVIEW
4
PASS
4
INFO
0
Probed from Madrid, Spain
301 Moved Permanently
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.

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 301-redirects to HTTPS

www / non-www

200https://www.ons.gov.uk/
200https://ons.gov.uk/

Inconsistent — duplicate content risk

HTTP → HTTPS

301http://ons.gov.uk/ https://www.ons.gov.uk/

Consistent

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

Certificate validity

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

Recommended actions

  • 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
A+
DNS Records
1 A records, 39 ms lookup
PASS
1 A records, 39 ms lookup
Info::
Resolves to 1 IPv4 address(es)
Got: 18.169.209.99
Info::
Single A record — no DNS redundancy
Multiple A records provide failover if one server goes down.
Info::
No IPv6 (AAAA) records
Info::
3 nameserver(s) configured
Got: ns1.bt.net, ns2.bt.net, ns0.bt.net
Info::
1 mail exchanger(s) configured
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: 39 ms
Got: 39 ms
A18.169.209.99
AAAA
CNAME
NSns1.bt.net, ns2.bt.net, ns0.bt.net
MX
0 ons-gov-uk.mail.protection.outlook.com
TXT
miro-verification=27f4614c78e7e5ca95026fda3f129de0cdd7115f
eyuWmArD1gHOtIbP9S8QUIYp8mzCKS4f67LziRdqdQIgiaKJA+Xn1RvqOJJfVFxv/yuoK52KSZi7uDay...
QuoVadis=7a067779-b648-4f55-b7cd-d22b35ca987e
airtable-verification=fe6fcbd53ab9c2ae9c3f39c3afd6aeb9
MS=ms21090673
atlassian-domain-verification=xSTx1WHy5mSzkLum90JXpNJqEaKyyPAi63SboeUwixsYifPnza...
QuoVadis=f5def41c-8f95-453c-850a-c3bb8424fb93
pexip-ms-tenant-domain-verification=73e0f7c4-5430-4c64-acfb-4012d58762aa
jamf-site-verification=c-Ekp4yzpzwQBgiLcHj6ow
apple-domain-verification=HiwZISvk85eEb5to
google-site-verification=Pa8IqEBwNpNpNy2z6Y6hWCjMWnVCntQXlGsz_hrFkyI
SPF v=spf1 include:extspf.ons.gov.uk include:spf.protection.outlook.com include:serv...
CAALookup not available with standard resolver
Resolved in 39 ms

Multiple A records provide failover if one server goes down.

Why this matters

Single A record means a single point of failure — if that IP goes down, your site is unreachable until DNS TTL expires.

Learn more

Add multiple A records for round-robin failover, or use a managed DNS provider with health-checked failover (Route 53, Cloudflare, NS1). Short TTL (60-300s) lets clients recover faster on outages.

Source: SRE practice / DNS architecture

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), 255 ms total
PASS
1 redirect(s), 255 ms total
Info::
Single redirect
Got: https://ons.gov.uk → https://www.ons.gov.uk/ (301)
Info::
WWW normalization redirect

https://ons.gov.uk

88 ms · HTTP/1.1

301

https://www.ons.gov.uk/

167 ms · HTTP/1.1 FINAL

#URLStatusTimeProtocolServer
1https://ons.gov.uk30188 msHTTP/1.1nginx
2https://www.ons.gov.uk/200167 msHTTP/1.1cloudflare

See the visual redirect chain in the HTTP Probe tab →

A+
Domain Intelligence
ons.gov.uk — via Office for National Statistics, 57 years, 1 months old, hosted on AWS
PASS
ons.gov.uk — via Office for National Statistics, 57 years, 1 months old, hosted on AWS
Info::
Domain registered until Feb 1, 2027 (9 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: Office for National Statistics
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: AWS
Got: AS16509
Domain expiry

231 days

February 1, 2027

SSL certificate

72 days

Issued by Let's Encrypt

Domain age

57 years, 1 months

Registered January 1, 1970

DNSSEC

Not enabled

Protects against DNS spoofing

Hosting

AWS

ASN AS16509

18.169.209.99

Registrar

Office for National Statistics

Unlocked 3 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 Office for National Statistics
Created January 1, 1970 (57 years, 1 months ago)
Expires February 1, 2027 (9 months)
Last Updated February 1, 2026
Name Servers ns0.bt.net, ns1.bt.net, ns2.bt.net
DNSSEC Not enabled
Registrant DST Resources
Hosting
IP Address 18.169.209.99
ASN AS16509 (AMAZON-02 - Amazon.com, Inc., US)
Provider AWS
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 126 ms — DNS, TCP, TLS, TTFB, content transfer breakdown
PASS
DNS Lookup DNS Lookup — time to resolve the domain name to an IP address.
40 ms
TCP Connect TCP Connect — time to establish a TCP connection to the server.
28 ms
TLS Handshake TLS Handshake — time to complete the HTTPS encryption handshake.
31 ms
Time to First Byte Time to First Byte — how long the server takes to respond with the first byte of data.
126 ms
Total Time Total request time from DNS lookup through full response.
127 ms

Connection waterfall

DNS Lookup 40 ms TCP Connect 28 ms TLS Handshake 31 ms Server Processing 28 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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