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https://nrel.gov

Infrastructure

· 9 checks — DNS, redirects, IPv6, crawlability, URL variants, and domain intelligence rolled into one auditable list.
SCORE
93
GRADE
A
FIX
0
REVIEW
2
PASS
7
INFO
0
Probed from Sao Paulo, Brazil
301 Moved Permanently
Checks
9
7 PASS 2 REVIEW
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: *

Allow:
sitemap.xml No sitemap found

No sitemap found

Adding a sitemap helps search engines discover your pages.

B
TLS Certificate Expiry & Recommendations
88 days until leaf cert expires — 2 issues to address
REVIEW

Certificate validity

88
days left
0d 30d 60d 90d+

Recommended actions

  • Add includeSubDomains to the HSTS directive
  • Enable OCSP stapling on your TLS server to remove a CA roundtrip and protect user privacy
A
DNS Records
2 A records, 992 ms lookup
PASS
2 A records, 992 ms lookup
Info::
Resolves to 2 IPv4 address(es)
Got: 104.17.147.107, 104.17.148.107
Info::
Has 2 IPv6 (AAAA) record(s)
Got: 2606:4700::6811:936b, 2606:4700::6811:946b
Info::
6 nameserver(s) configured
Got: ns1.nlr.gov, ns2.nlr.gov, adns1.es.net, adns2.es.net, helios.nrel.gov, phaeton.nrel.gov
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
Warning::
DNS resolution is slow (992 ms)
Slow DNS adds latency to every page load. Consider a faster DNS provider.
Got: 992 ms
A104.17.147.107, 104.17.148.107
AAAA2606:4700::6811:936b, 2606:4700::6811:946b
CNAME—
NSns1.nlr.gov, ns2.nlr.gov, adns1.es.net, adns2.es.net, helios.nrel.gov, phaeton.nrel.gov
MX
10 nrel-gov.mail.protection.outlook.com
TXT
MS=ms37983623
MS=ms71935541
nintex.5fb85f2f631e450068ced91f
nintex.6009faa1fd3d480069462e75
nintex.600f46136c33d700711f9bc1
_9v4cz6gjxipnimhgb2a8kwpzognsb99
_bri4mrz8qk1mb4kcidqshziqs6bppo1
_mgmv3e8es64eznlbmowqrzfqpkx8f5k
xl45t6dlh6tf6fx6lwz42jmwkzgfcr96
apple-domain-verification=diC3aAy41igcFTOb
SPF v=spf1 redirect=nrel.gov.hosted.spf-report.com
docker-verification=b9b70cea-8349-43ca-9216-bec930c297c2
have-i-been-pwned-verification=3b1c786c102c794204078c49f1a885f9
smartsheet-gov-site-validation=dsGSvQLrGcI5jyZMXP8KzcO69zhoFb9R
webexdomainverification.7KSKC=46db48a6-b9df-4624-8cf8-3fedeedadbbd
google-site-verification=4dmqBw_dgmtPgK46mMA0NH-nFZJmg9qqQGrYlUcCAX4
google-site-verification=O5CL3vIb5kp_T6QLPQC98JCWUNf4-2qn6VrQpGXI5f8
google-site-verification=SEt4fK2zVSVb2spRrHNzs51RQtK-kf78d85yKranVnQ
google-site-verification=jg69IUkkt0viAdafZnf6TBaoLMvwPzJ4PvMQtW_aQ4s
google-site-verification=soBdrDBzKJqc2c7lxrFMeNDYE-afan5T-zaSa_ymJXAa
SbcOjjqN9CaiUVMlUSxEopawqrv8awFWHA1JPoxfTjsqmWFcQ8gWb287/oHcmSKePsVbJbv8OnDz9ae8...
adobe-idp-site-verification=8fc8c70b1f7f883f3a1bb085ffabb441e1b13414e17757c459d7...
adobe-idp-site-verification=e52b6edba5a48ae678fd1967afe822fb6d3710877e0c03908c5f...
atlassian-domain-verification=CrOFA1oVcdJFaFAwALiRimW9Na7DMORCkwgKPFmWrC82GZ9Yy8...
figma-domain-verification=7b2cff20450f4241197cf04e3e996554720c887906416746708596...
figma-domain-verification=faee35477143bfd6686245092c7a02cb023080ba49a697b060ce31...
CAALookup not available with standard resolver
Resolved in 992 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.

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
1 redirect(s), 464 ms total
PASS
1 redirect(s), 464 ms total
Info::
Single redirect
Got: https://nrel.gov → https://www.nlr.gov/ (301)
Info::
WWW normalization redirect
Info::
Cross-domain redirect detected

https://nrel.gov

252 ms · HTTP/1.1

301

https://www.nlr.gov/

212 ms · HTTP/1.1 FINAL

#URLStatusTimeProtocolServer
1https://nrel.gov301252 msHTTP/1.1cloudflare
2https://www.nlr.gov/200212 msHTTP/1.1cloudflare

See the visual redirect chain in the HTTP Probe tab →

A+
IPv6 Readiness
IPv6 reachable (1 ms)
PASS
IPv6 reachable (1 ms)
Info::
IPv6 is configured and reachable at 2606:4700::6811:936b, 2606:4700::6811:946b
Got: 1 ms connect
IPv6 Ready
AAAA Records 2606:4700::6811:936b, 2606:4700::6811:946b Connection Reachable (1 ms)
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.nrel.gov/
200https://nrel.gov/

Preferred variant: non-www

HTTP → HTTPS

301http://nrel.gov/ → https://nrel.gov/

Consistent

A+
Domain Intelligence
nrel.gov — via get.gov, 28 years, 11 months old
PASS
nrel.gov — via get.gov, 28 years, 11 months old
Info::
Domain registered until Aug 25, 2026 (4 months remaining)
Info::
DNSSEC is enabled
Info::
Registrar: get.gov
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.
Domain expiry

73 days

August 25, 2026

SSL certificate

88 days

Issued by Let's Encrypt

Domain age

28 years, 11 months

Registered October 2, 1997

DNSSEC

Enabled

Protects against DNS spoofing

Hosting

Unknown

2606:4700::6811:936b

Registrar

get.gov

Unlocked 6 NS records
Expiry timeline
Today
+1 year
Domain expiry SSL expiry Danger zone (≤30 days)
Recommended actions
  • Renew the domain or enable auto-renewal to prevent accidental expiry
  • Enable registrar lock (clientTransferProhibited) to block unauthorized domain transfers
Registrar get.gov
Created October 2, 1997 (28 years, 11 months ago)
Expires August 25, 2026 (4 months)
Last Updated March 9, 2026
Name Servers adns1.es.net, adns2.es.net, helios.nrel.gov, ns1.nlr.gov, ns2.nlr.gov, phaeton.nrel.gov
DNSSEC Enabled
Registrant REDACTED FOR PRIVACY
Hosting
IP Address 2606:4700::6811:936b
Data source: rdap (0.7s)

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 420 ms — DNS, TCP, TLS, TTFB, content transfer breakdown
PASS
DNS Lookup DNS Lookup — time to resolve the domain name to an IP address.
317 ms
TCP Connect TCP Connect — time to establish a TCP connection to the server.
2 ms
TLS Handshake TLS Handshake — time to complete the HTTPS encryption handshake.
10 ms
Time to First Byte Time to First Byte — how long the server takes to respond with the first byte of data.
420 ms
Total Time Total request time from DNS lookup through full response.
420 ms

Connection waterfall

DNS Lookup 317 ms TCP Connect 2 ms TLS Handshake 10 ms Server Processing 92 ms Content Transfer 0 ms
A+
CDN & Delivery
Cloudflare (HIT)
PASS
Cloudflare (HIT)
Info::
Site is served via Cloudflare CDN (edge: GRU)
Got: cf-ray: 9f00373c2af1998e-GRU
Info::
CDN cache status: HIT
CDN Detected: Cloudflare
Provider Cloudflare Cache Status HIT Evidence cf-ray: 9f00373c2af1998e-GRU
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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