tele3.cz

We performed a comprehensive analysis of tele3.cz on 2026-06-29. The website returned an HTTP 200 status code with a server response time of 9461ms. The page is served over HTTP/1.1 protocol with Gzip compression enabled, achieving approximately 60.0% size reduction. The total page weight is 14 KB. The website uses a secure HTTPS connection with a valid SSL certificate issued by ZeroSSL GmbH (DV type). The connection is encrypted using TLS 1.2 with the ECDHE-ECDSA-AES128-GCM-SHA256 cipher suite and ECDSA-SHA256 signature algorithm. The certificate covers 2 domain(s) (Subject Alternative Names) and expires on 2026-09-03, which is 66 days from now. The security headers analysis reveals a score of 35/100 (below average). The following security headers are properly configured: Strict-Transport-Security (HSTS) and X-Frame-Options. However, the site is missing Content-Security-Policy, 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 1 technologies across 1 categories powering tele3.cz. The detected stack includes jQuery 2.1.4.. Based on our comprehensive analysis of domain age, SSL configuration, email authentication, security headers, and blacklist status, tele3.cz receives an overall trust score of 77/100, classified as "Likely Safe".

After conducting a thorough safety and legitimacy analysis, tele3.cz receives a trust score of 77/100, which places it in the "Likely Safe" 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, HSTS (HTTP Strict Transport Security) enforcement preventing protocol downgrade attacks, a valid SSL certificate issued by ZeroSSL GmbH with 66 days until expiration, SPF (Sender Policy Framework) email authentication preventing email spoofing, DMARC email authentication with a none policy, and DNSSEC providing authenticated DNS responses. Areas of concern include: the absence of a Content-Security-Policy header, which leaves the site more vulnerable to cross-site scripting (XSS) attacks, missing Referrer-Policy, potentially leaking URL information to third parties, and the domain's WHOIS information is hidden behind a privacy service, making it harder to verify the owner's identity. While these issues don't necessarily indicate malicious intent, they represent areas where the website's security posture could be improved. We checked tele3.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 tele3.cz and identified 1 distinct technologies across 1 categories. This analysis is performed by examining HTTP response headers, HTML source code patterns, JavaScript library fingerprints, CSS framework signatures, and DNS records. JavaScript Library: jQuery (version 2.1.4.) — provides utility functions and DOM manipulation for tele3.cz.

tele3.cz delivers its homepage in 9461ms (server response time), which is considered slow by industry standards. The total page weight is 14 KB, and we detected 115 resource requests loading assets from 4 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. The website uses Gzip compression for text-based assets, achieving an estimated 60.0% reduction in transfer size. This reduces bandwidth usage and improves page load times, especially for visitors on slower connections. Asset minification status: 0 out of 6 CSS files and 4 out of 10 JavaScript files are minified. Minifying the remaining 12 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 tele3.cz produces approximately 0.01g 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 14 KB is the primary factor in this calculation. Core Web Vitals data from the Chrome User Experience Report (CrUX) is not available for tele3.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.

tele3.cz resolves to the IPv4 address 81.0.217.1 and also supports IPv6 (2001:1528:123:123::123), demonstrating modern network infrastructure readiness. The domain has 1 A record(s) configured. The domain name system is managed by 3 name servers: ns1.tele3.cz, ns2.tele3.cz, and ns3.tele3.eu. Having 3 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 tele3.cz is handled by tele3.cz with 1 MX records configured: mail.tele3.cz. Multiple MX records provide failover redundancy — if the primary mail server is unavailable, email will be routed to the next available server. SPF (Sender Policy Framework) is configured, which specifies which mail servers are authorized to send email on behalf of this domain. This helps prevent email spoofing and improves email deliverability. DMARC (Domain-based Message Authentication, Reporting and Conformance) is configured with a none policy — a monitoring-only setting that doesn't enforce any action on unauthorized emails. DKIM was not detected. Without DKIM, recipients cannot cryptographically verify that emails claiming to be from this domain are authentic. DNSSEC is enabled for tele3.cz, providing an additional layer of security by cryptographically signing DNS records. This prevents DNS cache poisoning and man-in-the-middle attacks that could redirect visitors to malicious websites.

The homepage of tele3.cz contains 218 words of visible text content. This is a relatively short page — adding more descriptive content could improve search engine visibility. The page is structured with 10 H2 headings, 0 H3 headings, 0 H4 headings. The page includes 24 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 68 internal links pointing to other pages on the same domain and 4 external links pointing to third-party websites. There are 10 external JavaScript files, 6 CSS stylesheets, and 0 iframes on the page. The site implements the following web standards and features: XML Sitemap (helps search engines discover all pages), robots.txt (controls search engine crawling behavior), and RSS feed for content syndication. Notable missing features: Schema.org structured data. Adding these could improve search engine discoverability and rich result eligibility. We detected the following payment methods accepted on tele3.cz: Visa and Mastercard. 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 2 platforms: Twitter (@tele3) and Linkedin (@tele3-s-r-o-). An active social media presence is a positive trust indicator and helps build brand awareness and customer engagement.

The title tag for tele3.cz is well-optimized at 57 characters: "TELE3 | registrace domén | webhosting | virtuální servery". The length falls within the ideal range for Google search results, ensuring the full title is displayed without truncation. The meta description is 146 characters (well-optimized): "Komplexní internetová řešení od TELE3 - registrace domén, webhosting, serverhosting, VPS, virtuální servery, správa serv...". 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 cs, the meta robots directive is set to index,follow, and a favicon is configured. No Open Graph tags are configured. When someone shares a link to tele3.cz on social media, the platform will have to guess the title, description, and image — often producing unattractive or inaccurate previews. Adding OG tags is essential for social media marketing. The meta keywords tag contains 8 terms including registrace domén, webhosting, virtuální servery, VPS, and serverhosting. 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.