c3l.se

We performed a comprehensive analysis of c3l.se on 2026-06-28. The website returned an HTTP 200 status code with a server response time of 6878ms. The page is served over HTTP/1.1 protocol with Gzip compression enabled, achieving approximately 60.0% size reduction. The total page weight is 63 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 30/100 (below average). The following security headers are properly configured: X-Frame-Options and Referrer-Policy. However, the site is missing Content-Security-Policy, Strict-Transport-Security (HSTS), X-Content-Type-Options, 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 2 technologies across 2 categories powering c3l.se. The detected stack includes React and jQuery. The UI is built with React. Based on our comprehensive analysis of domain age, SSL configuration, email authentication, security headers, and blacklist status, c3l.se receives an overall trust score of 63/100, classified as "Likely Safe".

After conducting a thorough safety and legitimacy analysis, c3l.se receives a trust score of 63/100, 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, SPF (Sender Policy Framework) email authentication preventing email spoofing, 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 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 c3l.se 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 c3l.se and identified 2 distinct technologies across 2 categories. This analysis is performed by examining HTTP response headers, HTML source code patterns, JavaScript library fingerprints, CSS framework signatures, and DNS records. UI Library: React — handles the user interface rendering and component management for c3l.se. JavaScript Library: jQuery — provides utility functions and DOM manipulation for c3l.se.

c3l.se delivers its homepage in 6878ms (server response time), which is considered slow by industry standards. The total page weight is 63 KB, and we detected 106 resource requests loading assets from 5 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 11 CSS files and 0 out of 13 JavaScript files are minified. Minifying the remaining 24 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 c3l.se produces approximately 0.03g 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 63 KB is the primary factor in this calculation. Core Web Vitals data from the Chrome User Experience Report (CrUX) is not available for c3l.se. 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.

c3l.se resolves to the IPv4 address 185.84.52.125, 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: ns1.loopia.se and ns2.loopia.se. 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 c3l.se is handled by loopia.se with 2 MX records configured: mailcluster.loopia.se and mail2.loopia.se. 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 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 enabled for c3l.se, 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. Our subdomain enumeration scan discovered 25 active subdomains for c3l.se: admin.c3l.se, api.c3l.se, app.c3l.se, apps.c3l.se, blog.c3l.se, cdn.c3l.se, community.c3l.se, and dev.c3l.se. Plus 17 additional subdomains. Active subdomains can reveal the organization's infrastructure, including development environments, API endpoints, and third-party service integrations.

The homepage of c3l.se contains 330 words of visible text content. This is a moderate amount of content. The page is structured with 4 H2 headings, 0 H3 headings, 11 H4 headings. The page includes 13 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 57 internal links pointing to other pages on the same domain and 4 external links pointing to third-party websites. There are 13 external JavaScript files, 11 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). Notable missing features: robots.txt and Schema.org structured data. Adding these could improve search engine discoverability and rich result eligibility. The website has social media presence across 1 platforms: Facebook (@tyresokomvux). An active social media presence is a positive trust indicator and helps build brand awareness and customer engagement.

The title tag for c3l.se is good at 22 characters: "C3L.se - Tyresö kommun". The length is acceptable, though it may be slightly truncated in some search result displays. The meta description is 143 characters (well-optimized): "C3L - Tyresö komvux bedriver kommunal vuxenutbildning i Tyresö. Hos oss kan du läsa såväl grundläggande som gymnasiala k...". 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 canonical url is correctly set to https://www.tyreso.se/komvux.html, preventing duplicate content issues, the page language is declared as sv, and a favicon is configured. Open Graph meta tags are configured with 2/4 recommended fields: OG title ("Komvux..."), OG description, 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 1 terms including Tyresö. 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.