stk.cz

We performed a comprehensive analysis of stk.cz on 2026-07-05. The website returned an HTTP 200 status code with a server response time of 7204ms. The page is served over HTTP/1.1 protocol, however no compression (Gzip or Brotli) is enabled, which means the page is transferred at its full uncompressed size. The total page weight is 110 KB. Warning: The website does not have a valid SSL certificate. Visitors may see security warnings in their browser, and data transmitted to and from this website is not encrypted. The security headers analysis reveals a score of 20/100 (poor). The following security headers are properly configured: Strict-Transport-Security (HSTS). However, the site is missing Content-Security-Policy, X-Frame-Options, X-Content-Type-Options, Referrer-Policy, and Permissions-Policy, which could expose the site and its users to cross-site scripting (XSS), clickjacking, and other web-based attacks. Our technology detection scan identified 3 technologies across 3 categories powering stk.cz. The detected stack includes Vite, Matomo, and jQuery. Based on our comprehensive analysis of domain age, SSL configuration, email authentication, security headers, and blacklist status, stk.cz receives an overall trust score of 57/100, classified as "Caution Advised".

After conducting a thorough safety and legitimacy analysis, stk.cz receives a trust score of 57/100, which places it in the "Caution Advised" category. This score is calculated by evaluating multiple factors including SSL certificate validity, domain registration history, email authentication protocols, security header configuration, and blacklist status across major threat intelligence databases. The analysis identified several positive trust signals: a valid HTTPS connection protecting data in transit and HSTS (HTTP Strict Transport Security) enforcement preventing protocol downgrade attacks. Areas of concern include: the absence of a Content-Security-Policy header, which leaves the site more vulnerable to cross-site scripting (XSS) attacks, no X-Frame-Options header, which could allow the site to be embedded in malicious iframes (clickjacking), missing Referrer-Policy, potentially leaking URL information to third parties, the domain's WHOIS information is hidden behind a privacy service, making it harder to verify the owner's identity, and DNSSEC is not enabled, leaving DNS queries vulnerable to spoofing attacks. While these issues don't necessarily indicate malicious intent, they represent areas where the website's security posture could be improved. We checked stk.cz against 8 major blacklist databases including Google Safe Browsing, Phishtank, Urlhaus, Openphish, Dnsfilter, Spamhaus Dbl, Surbl, and Virustotal. The domain passed all 8 checks with a clean status, meaning it has not been flagged for phishing, malware distribution, spam, or other malicious activities by any of the tested threat intelligence providers.

Our technology detection engine scanned stk.cz and identified 3 distinct technologies across 3 categories. This analysis is performed by examining HTTP response headers, HTML source code patterns, JavaScript library fingerprints, CSS framework signatures, and DNS records. Build Tool: Vite — bundles and optimizes the JavaScript and CSS assets for stk.cz. Analytics: Matomo — tracks visitor behavior and provides traffic insights for stk.cz. JavaScript Library: jQuery — provides utility functions and DOM manipulation for stk.cz.

stk.cz delivers its homepage in 7204ms (server response time), which is considered slow by industry standards. The total page weight is 110 KB, and we detected 457 resource requests loading assets from 22 third-party domains. A high number of third-party domains can significantly impact page load time due to additional DNS lookups and TLS handshakes required for each domain. No compression is currently enabled on stk.cz. Enabling Brotli or Gzip compression could reduce page size by 60-80% for text-based assets (HTML, CSS, JavaScript), significantly improving load times and reducing bandwidth costs. This is one of the simplest and most impactful performance optimizations available. Asset minification status: 2 out of 2 CSS files and 4 out of 6 JavaScript files are minified. Minifying the remaining 2 unminified file(s) could further reduce page weight by 10-30% for those assets. Minification is a best practice that reduces download sizes without affecting functionality. From an environmental perspective, each page view of stk.cz produces approximately 0.05g of CO₂, earning a carbon rating of A. This places the website among the cleanest on the web, demonstrating efficient use of server resources and optimized content delivery. For reference, the average web page produces about 0.5g of CO₂ per page view. The page weight of 110 KB is the primary factor in this calculation. Core Web Vitals data from the Chrome User Experience Report (CrUX) is not available for stk.cz. This typically means the site doesn't have enough real-world Chrome user traffic to generate statistically significant field data, or the domain is not included in the CrUX dataset. Core Web Vitals (LCP, INP, CLS) are important Google ranking factors that measure real user experience.

stk.cz resolves to the IPv4 address 195.113.241.64, but does not support IPv6. IPv6 adoption is increasingly important as IPv4 address space becomes exhausted, and some ISPs and regions are transitioning to IPv6-only connectivity. The domain has 1 A record(s) configured. The domain name system is managed by 2 name servers: ns.techlib.cz and nsa.ces.net. Having 2 name servers provides good redundancy — if one fails, the others can continue serving DNS queries. The choice of name servers often indicates the DNS hosting provider or CDN service being used. Email for stk.cz is handled by techlib.cz with 1 MX records configured: ns.techlib.cz. Multiple MX records provide failover redundancy — if the primary mail server is unavailable, email will be routed to the next available server. SPF is not configured, meaning any server could potentially send emails pretending to be from this domain. This is a significant email security concern. DMARC is not configured, leaving the domain vulnerable to email spoofing and phishing attacks that impersonate this domain. DKIM was not detected. Without DKIM, recipients cannot cryptographically verify that emails claiming to be from this domain are authentic. DNSSEC is not enabled for stk.cz. While not critical for most websites, DNSSEC adds an important security layer by ensuring DNS responses haven't been tampered with during transit. Enabling DNSSEC is recommended for domains handling sensitive data or financial transactions.

The homepage of stk.cz contains 1,159 words of visible text content. This is a substantial amount of content that provides good opportunities for search engine indexing. The page is structured with 1 H2 headings, 17 H3 headings, 72 H4 headings. The page includes 80 images. All images have proper alt text attributes ✓, which is excellent for both accessibility (screen readers) and SEO (search engines can understand image content). The link structure consists of 180 internal links pointing to other pages on the same domain and 185 external links pointing to third-party websites. The high number of internal links suggests a well-interconnected site structure, which helps search engines discover and crawl all pages efficiently. There are 6 external JavaScript files, 2 CSS stylesheets, and 0 iframes on the page. The site implements the following web standards and features: RSS feed for content syndication. Notable missing features: XML Sitemap, robots.txt, and Schema.org structured data. Adding these could improve search engine discoverability and rich result eligibility. We detected the following payment methods accepted on stk.cz: Discover. Offering multiple payment options including credit cards and digital wallets improves customer trust and can increase conversion rates. The website has social media presence across 3 platforms: Facebook (@ntkcz), Twitter (@ntkcz), and Instagram (@ntkcz). An active social media presence is a positive trust indicator and helps build brand awareness and customer engagement.

The title tag for stk.cz is well-optimized at 36 characters: "Czech National Library of Technology". The length falls within the ideal range for Google search results, ensuring the full title is displayed without truncation. The meta description is 26 characters (acceptable): "Národní technická knihovna". Google typically displays up to 155-160 characters of the meta description in search results. A compelling meta description with a clear call-to-action can significantly improve click-through rates from search results. The page language is declared as en and the meta robots directive is set to noindex, nofollow. Open Graph meta tags are configured with 3/4 recommended fields: OG title ("English..."), OG image (social sharing thumbnail), OG type (non_profit). These tags control how the page appears when shared on Facebook, LinkedIn, and other social media platforms that support the Open Graph protocol. The meta keywords tag contains 7 terms including Knihovna, Praha, technická, NTK, and knihy. Note: Google has officially confirmed that it does not use the meta keywords tag as a ranking signal. However, some other search engines (Bing, Yandex) may still reference it.