Technical Information
| HTTP Status Code | 200 |
| HTTP Version | HTTP/1.1 |
| HTTPS | ✔ Available |
| IP Address | 18.245.199.104 |
| Server Software | Apache/2.4.58 (Ubuntu) |
| CDN | CDN (Hit from cloudfront) |
| Compression | gzip |
|
ℹ 🔵 Missing X-Frame-Options | The site can be embedded in iframes by third parties (clickjacking risk). |
HTTP Status Code 200
HTTP Version HTTP/1.1
HTTPS ✔ Available
IP Address 18.245.199.104
Server Software Apache/2.4.58 (Ubuntu)
CDN CDN (Hit from cloudfront)
Compression gzip
ℹ 🔵 Missing X-Frame-Options The site can be embedded in iframes by third parties (clickjacking risk).
Redirect Chain
| # | URL | HTTP Status Code | Status |
| 1 | https://ck12.org:443 | 301 | HTTP/2 301 |
| 2 | https://www.ck12.org/ | 302 | HTTP/2 302 |
| 3 | https://www.ck12.org/student/ | 200 | HTTP/2 200 |
#1 URL https://ck12.org:443
HTTP Status Code 301
Status HTTP/2 301
#2 URL https://www.ck12.org/
HTTP Status Code 302
Status HTTP/2 302
#3 URL https://www.ck12.org/student/
HTTP Status Code 200
Status HTTP/2 200
Performance
| DNS Lookup | 4.1 ms |
| TCP Connect | 5.3 ms |
| TLS Handshake | 4.9 ms |
| Time To First Byte (TTFB) | 16.7 ms |
| Content Download | 0.1 ms |
| Total Response Time | 16.9 ms |
DNS Lookup 4.1 ms
TCP Connect 5.3 ms
TLS Handshake 4.9 ms
Time To First Byte (TTFB) 16.7 ms
Content Download 0.1 ms
Total Response Time 16.9 ms
Security
| HTTPS | ✔ Enabled |
| HSTS | ✔ max-age=31536000; includeSubDomains; preload |
| CSP | ✔ Configured |
| X-Frame-Options | ⚠ Not configured |
| X-Content-Type-Options | ✔ nosniff |
| Referrer Policy | strict-origin-when-cross-origin |
| HTTP/2 | ⚠ HTTP/1.1 |
HTTPS ✔ Enabled
HSTS ✔ max-age=31536000; includeSubDomains; preload
CSP ✔ Configured
X-Frame-Options ⚠ Not configured
X-Content-Type-Options ✔ nosniff
Referrer Policy strict-origin-when-cross-origin
HTTP/2 ⚠ HTTP/1.1
SEO Quick Check
Title CK12-Foundation
Detected Technologies
| Technology | Google Analytics Apache |
Technology Google Analytics Apache
HTTP Headers
| Content-type
| text/html; charset=utf-8 |
| Date
| Wed, 19 Aug 2026 18:34:59 GMT |
| Server
| Apache/2.4.58 (Ubuntu) |
| Content-encoding
| gzip |
| X-content-type-options
| nosniff |
| Referrer-policy
| strict-origin-when-cross-origin |
| Vary
| Accept-Encoding |
| Via
| 1.1 aa9f58294a12ad740a4864bf7ef145ac.cloudfront.net (CloudFront) |
| Alt-svc
| h3=":443"; ma=86400 |
| Age
| 12860 |
| Content-security-policy
| frame-ancestors 'self' https://*.ck12.org chrome-extension://necpjbiijgficbgfanibojgkcbbooicg; report-uri https://csp-report.ck12.org; report-to ck12-csp-endpoint; |
| Report-to
| { "group": "ck12-csp-endpoint","max_age": 86400,"endpoints": [{ "url": " https://csp-report.ck12.org" }] } |
| Reporting-endpoints
| ck12-csp-endpoint="https://csp-report.ck12.org" |
| Strict-transport-security
| max-age=31536000; includeSubDomains; preload |
| Set-cookie
| flxweb_role=student; Domain=ck12.org; Max-Age=604800; Path=/; expires=Wed, 26-Aug-2026 18:34:59 GMT; secure |
| X-cache
| Hit from cloudfront |
| X-amz-cf-pop
| CDG50-P6 |
| X-amz-cf-id
| IzitwyRJShTphi9SMCWNsUb_BwTbdjD9SyXC2G9NlSywiaU-k4LVSg== |
Meta Tags
| Fb:app_id | 159884644067996 |
| Viewport | width=device-width, initial-scale=1, minimum-scale=1.0 |
| Google-site-verification | wHx0f-Udlfd7ZNYNrIXpJVpjjO8nSH5RE0jIX8V-jIM |
| Application-name | CK-12 Foundation |
| Msapplication-TileColor | #003300 |
| Msapplication-TileImage |  |
Content-type text/html; charset=utf-8
Date Wed, 19 Aug 2026 18:34:59 GMT
Server Apache/2.4.58 (Ubuntu)
Content-encoding gzip
X-content-type-options nosniff
Referrer-policy strict-origin-when-cross-origin
Vary Accept-Encoding
Via 1.1 aa9f58294a12ad740a4864bf7ef145ac.cloudfront.net (CloudFront)
Alt-svc h3=":443"; ma=86400
Age 12860
Content-security-policy frame-ancestors 'self' https://*.ck12.org chrome-extension://necpjbiijgficbgfanibojgkcbbooicg; report-uri https://csp-report.ck12.org; report-to ck12-csp-endpoint;
Report-to { "group": "ck12-csp-endpoint","max_age": 86400,"endpoints": [{ "url": " https://csp-report.ck12.org" }] }
Reporting-endpoints ck12-csp-endpoint="https://csp-report.ck12.org"
Strict-transport-security max-age=31536000; includeSubDomains; preload
Set-cookie flxweb_role=student; Domain=ck12.org; Max-Age=604800; Path=/; expires=Wed, 26-Aug-2026 18:34:59 GMT; secure
X-cache Hit from cloudfront
X-amz-cf-pop CDG50-P6
X-amz-cf-id IzitwyRJShTphi9SMCWNsUb_BwTbdjD9SyXC2G9NlSywiaU-k4LVSg==
