Technical Information
| HTTP Status Code | 200 |
| HTTP Version | HTTP/1.1 |
| HTTPS | ✔ Available |
| IP Address | 194.164.198.54 |
| Server Software | nginx/1.24.0 (Ubuntu) |
| CDN | CDN (HIT, MISS) |
| Compression | gzip |
|
🔒 🟡 Mixed Content (6 HTTP resources) | The page is served over HTTPS but loads 6 resource(s) over HTTP. This may be blocked in modern browsers. |
|
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 194.164.198.54
Server Software nginx/1.24.0 (Ubuntu)
CDN CDN (HIT, MISS)
Compression gzip
🔒 🟡 Mixed Content (6 HTTP resources) The page is served over HTTPS but loads 6 resource(s) over HTTP. This may be blocked in modern browsers.
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://swi-prolog.org:443 | 301 | HTTP/1.1 301 Moved Permanently |
| 2 | https://www.swi-prolog.org/ | 200 | HTTP/2 200 |
#1 URL https://swi-prolog.org:443
HTTP Status Code 301
Status HTTP/1.1 301 Moved Permanently
#2 URL https://www.swi-prolog.org/
HTTP Status Code 200
Status HTTP/2 200
Performance
| DNS Lookup | 51.3 ms |
| TCP Connect | 52.5 ms |
| TLS Handshake | 7.1 ms |
| Time To First Byte (TTFB) | 194.7 ms |
| Content Download | 0.2 ms |
| Total Response Time | 194.9 ms |
DNS Lookup 51.3 ms
TCP Connect 52.5 ms
TLS Handshake 7.1 ms
Time To First Byte (TTFB) 194.7 ms
Content Download 0.2 ms
Total Response Time 194.9 ms
Security
| HTTPS | ✔ Enabled |
| HSTS | ✔ max-age=900 |
| CSP | ✔ Configured |
| X-Frame-Options | ⚠ Not configured |
| X-Content-Type-Options | ⚠ Not configured |
| HTTP/2 | ⚠ HTTP/1.1 |
HTTPS ✔ Enabled
HSTS ✔ max-age=900
CSP ✔ Configured
X-Frame-Options ⚠ Not configured
X-Content-Type-Options ⚠ Not configured
HTTP/2 ⚠ HTTP/1.1
SEO Quick Check
Title SWI-Prolog
Detected Technologies
| Technology | Google Analytics Nginx |
Technology Google Analytics Nginx
HTTP Headers
| Server
| nginx/1.24.0 (Ubuntu) |
| Content-type
| text/html; charset=UTF-8 |
| Content-security-policy
| frame-ancestors 'none' |
| Content-encoding
| gzip |
| Via
| 1.1 varnish, 1.1 varnish |
| Accept-ranges
| bytes |
| Age
| 0 |
| Date
| Fri, 24 Jul 2026 09:06:22 GMT |
| X-served-by
| cache-bfi-krnt7300056-BFI, cache-par-lfpb1150027-PAR |
| X-cache
| HIT, MISS |
| X-cache-hits
| 9, 0 |
| X-timer
| S1784883983.695698,VS0,VE134 |
| Strict-transport-security
| max-age=900 |
| Content-length
| 3729 |
Meta Tags
| Content-type | text/html; charset=UTF-8 |
Server nginx/1.24.0 (Ubuntu)
Content-type text/html; charset=UTF-8
Content-security-policy frame-ancestors 'none'
Content-encoding gzip
Via 1.1 varnish, 1.1 varnish
Accept-ranges bytes
Age 0
Date Fri, 24 Jul 2026 09:06:22 GMT
X-served-by cache-bfi-krnt7300056-BFI, cache-par-lfpb1150027-PAR
X-cache HIT, MISS
X-cache-hits 9, 0
X-timer S1784883983.695698,VS0,VE134
Strict-transport-security max-age=900
Content-length 3729
