Skip to content
https://www.khanacademy.org

Infrastructure

· 9 checks — DNS, redirects, IPv6, crawlability, URL variants, and domain intelligence rolled into one auditable list.
SCORE
80
GRADE
B
FIX
1
REVIEW
5
PASS
3
INFO
0
Probed from Madrid, Spain
200 OK
Checks
9
3 PASS 5 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
DNS Records
4 A records, 24 ms lookup
REVIEW
4 A records, 24 ms lookup
Info::
Resolves to 4 IPv4 address(es)
Got: 151.101.129.42, 151.101.193.42, 151.101.65.42, 151.101.1.42
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: prod.khan.map.fastly.net
Info::
No NS records found
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: 24 ms
Got: 24 ms
A151.101.129.42, 151.101.193.42, 151.101.65.42, 151.101.1.42
AAAA
CNAMEprod.khan.map.fastly.net
NS
MX
TXT
CAALookup not available with standard resolver
Resolved in 24 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)

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

C
Crawlability
Action
robots.txt present, sitemap with 0 URLs
REVIEW
robots.txt present, sitemap with 0 URLs
Info::
robots.txt is present
Got: 3101 bytes
Info::
sitemap.xml is present
Warning::
sitemap.xml contains invalid XML
Search engines may not be able to parse the sitemap. Fix XML validation errors.
Warning::
sitemap.xml is empty — no URLs found
An empty sitemap provides no value. Add <url> entries for your pages.
Info::
robots.txt does not reference a sitemap
Add a 'Sitemap:' directive to robots.txt so search engines can discover your sitemap.

Search engines may not be able to parse the sitemap. Fix XML validation errors.

Why this matters

An unparseable sitemap is silently ignored by Google — the URLs it advertises are never queued for crawl.

Learn more

Google's sitemap parser is strict about XML validity. A single unescaped `&` or unclosed tag invalidates the whole file. Run your sitemap through a validator (Search Console's Sitemaps report flags it) and fix the offending entry. Most generators escape correctly; mistakes usually come from manually-written entries.

Source: sitemaps.org / Google Search Central

An empty sitemap provides no value. Add <url> entries for your pages.

Why this matters

An empty sitemap signals 'no content to index' to Google — actively harmful versus having no sitemap at all.

Learn more

Google compares URLs in the sitemap against URLs it has crawled. An empty sitemap on a site with thousands of pages signals abandonment. Either populate it correctly (most CMSes auto-generate) or delete the file and let Google crawl normally.

Source: Google Search Central / sitemaps.org

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 3101 B Sitemaps referenced 0 User-agents Blocking No — crawling allowed
<!DOCTYPE html>
<html lang="en">
  <head>
    <meta
      http-equiv="Content-Security-Policy"
      content="default-src 'self'; img-src 'self' data:; media-src 'self' data:; object-src 'none'; style-src 'self' 'sha256-o4vzfmmUENEg4chMjjRP9EuW9ucGnGIGVdbl8d0SHQQ='; script-src 'self' 'sha256-KXex2o39zxtnzVWK4H5rW07g2+BlwSPtn+aguzsWkNg=';"
    />
    <link
      href="/_fs-ch-1T1wmsGaOgGaSxcX/assets/inter-var.woff2"
      rel="preload"
      as="font"
      type="font/woff2"
      crossorigin
    />
    <link href="/_fs-ch-1T1wmsGaOgGaSxcX/assets/styles.css" rel="stylesheet" />
    <meta name="viewport" content="width=device-width, initial-scale=1" />
    <title>Client Challenge</title>
    <style>
      #loading-error {
        font-size: 16px;
        font-family: 'Inter', sans-serif;
        margin-top: 10px;
        margin-left: 10px;
        display: none;
      }
    </style>
  </head>
  <body>
    <noscript>
      <div class="noscript-container">
        <div class="noscript-content">
          <img
            src="/_fs-ch-1T1wmsGaOgGaSxcX/assets/errorIcon.svg"
            alt=""
            role="presentation"
            class="error-icon"
          />
          <span class="noscript-span"
            >JavaScript is disabled in your browser.</span
          >
          <p>Please enable JavaScript to proceed.</p>
        </div>
      </div>
    </noscript>
    <div id="loading-error" role="alert" aria-live="polite">
      A required part of this site couldn’t load. This may be due to a browser
      extension, network issues, or browser settings. Please check your
      connection, disable any ad blockers, or try using a different browser.
    </div>
    <script>
      function loadScript(src) {
        return new Promise((resolve, reject) => {
          const script = document.createElement('script');
          script.onload = resolve;
          script.onerror = (event) => {
            console.error('Script load error event:', event);
            document.getElementById('loading-error').style.display = 'block';
            loadingError.setAttribute('aria-hidden', 'false');
            reject(
              new Error(
                `Failed to load script: ${src}, Please contact the service administrator.`
              )
            );
          };
          script.src = src;
          document.body.appendChild(script);
        });
      }

      loadScript('/_fs-ch-1T1wmsGaOgGaSxcX/errors.js')
        .then(() => {
          const script = document.createElement('script');
          script.src = '/_fs-ch-1T1wmsGaOgGaSxcX/script.js?reload=true';
          script.onerror = (event) => {
            console.error('Script load error event:', event);
            const errorMsg = new Error(
              `Failed to load script: ${script.src}. Please contact the service administrator.`
            );
            console.error(errorMsg);
            handleScriptError();
          };
          document.body.appendChild(script);
        })
        .catch((error) => {
          console.error(error);
        });
    </script>
  </body>
</html>

sitemap.xml 200 OK
Type URL Set URLs 0 entries Valid XML No
B
URL Variants
www/non-www, trailing slash, HTTP→HTTPS
REVIEW
www/non-www, trailing slash, HTTP→HTTPS
Critical::
HTTP version does not redirect to HTTPS
Got: HTTP 200 Expected: 301 redirect to HTTPS

www / non-www

200https://www.khanacademy.org/
308https://khanacademy.org/

HTTP → HTTPS

200http://www.khanacademy.org/

HTTP version does not redirect to HTTPS

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

Certificate validity

63
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+
Redirect Chain
No redirects — direct access
PASS
No redirects — direct access
Info::
No redirects — direct access
Got: https://www.khanacademy.org

https://www.khanacademy.org

124 ms · HTTP/1.1 FINAL

#URLStatusTimeProtocolServer
1https://www.khanacademy.org200124 msHTTP/1.1
A+
Domain Intelligence
khanacademy.org — via GoDaddy.com, LLC, 20 years, 4 months old, hosted on AWS
PASS
khanacademy.org — via GoDaddy.com, LLC, 20 years, 4 months old, hosted on AWS
Info::
Domain registered until Mar 14, 2029 (2 years, 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: GoDaddy.com, LLC
Info::
Hosting: AWS
Got: AS16509
Domain expiry

941 days

March 14, 2029

SSL certificate

63 days

Issued by GlobalSign nv-sa

Domain age

20 years, 4 months

Registered March 14, 2006

DNSSEC

Not enabled

Protects against DNS spoofing

Hosting

AWS

ASN AS16509

3.165.190.64

Registrar

GoDaddy.com, LLC

Lock status unknown 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
Registrar GoDaddy.com, LLC
Created March 14, 2006 (20 years, 4 months ago)
Expires March 14, 2029 (2 years, 11 months)
Last Updated July 4, 2024
Name Servers ns-1489.awsdns-58.org, ns-125.awsdns-15.com, ns-1664.awsdns-16.co.uk, ns-798.awsdns-35.net
DNSSEC Not enabled
Hosting
IP Address 3.165.190.64
ASN AS16509 (AMAZON-02 - Amazon.com, Inc., US)
Provider AWS
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

A+
HTTP Probe Timing
Total 153 ms — DNS, TCP, TLS, TTFB, content transfer breakdown
PASS
DNS Lookup DNS Lookup — time to resolve the domain name to an IP address.
47 ms
TCP Connect TCP Connect — time to establish a TCP connection to the server.
0 ms
TLS Handshake TLS Handshake — time to complete the HTTPS encryption handshake.
2 ms
Time to First Byte Time to First Byte — how long the server takes to respond with the first byte of data.
153 ms
Total Time Total request time from DNS lookup through full response.
153 ms

Connection waterfall

DNS Lookup 47 ms TCP Connect 0 ms TLS Handshake 2 ms Server Processing 103 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.

Send Feedback