Technical Information
| HTTP Status Code | 200 |
| HTTP Version | HTTP/1.1 |
| HTTPS | ✔ Available |
| IP Address | 151.101.121.91 |
| Server Software | Google Frontend |
| CDN | CDN (MISS, HIT) |
| Compression | gzip |
HTTP Status Code 200
HTTP Version HTTP/1.1
HTTPS ✔ Available
IP Address 151.101.121.91
Server Software Google Frontend
CDN CDN (MISS, HIT)
Compression gzip
Redirect Chain
| # | URL | HTTP Status Code | Status |
| 1 | https://developer.mozilla.org:443 | 302 | HTTP/2 302 |
| 2 | https://developer.mozilla.org/en-US/ | 200 | HTTP/2 200 |
#1 URL https://developer.mozilla.org:443
HTTP Status Code 302
Status HTTP/2 302
#2 URL https://developer.mozilla.org/en-US/
HTTP Status Code 200
Status HTTP/2 200
Performance
| DNS Lookup | 1.7 ms |
| TCP Connect | 2.9 ms |
| TLS Handshake | 6.9 ms |
| Time To First Byte (TTFB) | 13.4 ms |
| Content Download | 0.7 ms |
| Total Response Time | 14.1 ms |
DNS Lookup 1.7 ms
TCP Connect 2.9 ms
TLS Handshake 6.9 ms
Time To First Byte (TTFB) 13.4 ms
Content Download 0.7 ms
Total Response Time 14.1 ms
Security
| HTTPS | ✔ Enabled |
| HSTS | ✔ max-age=63072000 |
| CSP | ✔ Configured |
| X-Frame-Options | ✔ DENY |
| X-Content-Type-Options | ✔ nosniff |
| Referrer Policy | strict-origin-when-cross-origin |
| HTTP/2 | ⚠ HTTP/1.1 |
HTTPS ✔ Enabled
HSTS ✔ max-age=63072000
CSP ✔ Configured
X-Frame-Options ✔ DENY
X-Content-Type-Options ✔ nosniff
Referrer Policy strict-origin-when-cross-origin
HTTP/2 ⚠ HTTP/1.1
SEO Quick Check
| Title | MDN Web Docs |
| Meta Description | The MDN Web Docs site provides information about Open Web technologies including HTML, CSS, and APIs for both Web sites and progressive web apps. |
| Canonical | https://developer.mozilla.org/en-US/ |
| Open Graph Title | MDN Web Docs |
| Open Graph Description | The MDN Web Docs site provides information about Open Web technologies including HTML, CSS, and APIs for both Web sites and progressive web apps. |
| Open Graph Image | https://developer.mozilla.org/mdn-social-image.46ac2375.png |
| Twitter Card | summary |
Title MDN Web Docs Meta Description The MDN Web Docs site provides information about Open Web technologies including HTML, CSS, and APIs for both Web sites and progressive web apps. Canonical https://developer.mozilla.org/en-US/ Open Graph Title MDN Web Docs Open Graph Description The MDN Web Docs site provides information about Open Web technologies including HTML, CSS, and APIs for both Web sites and progressive web apps. Open Graph Image https://developer.mozilla.org/mdn-social-image.46ac2375.png Twitter Card summary Detected Technologies
| Technology | Google Analytics Node.js Stripe |
Technology Google Analytics Node.js Stripe
HTTP Headers
| Server
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| Expires
| Wed, 19 Aug 2026 02:31:25 GMT |
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| Date
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Meta Tags
| Viewport | width=device-width, initial-scale=1.0 |
| Description | The MDN Web Docs site provides information about Open Web technologies including HTML, CSS, and APIs for both Web sites and progressive web apps. |
| Position | 1 |
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