class101.net

We performed a comprehensive analysis of class101.net on 2026-07-06. The website returned an HTTP 200 status code with a server response time of 17855ms. The page is served over HTTP/2 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 982 KB, and the site is served behind a CDN (Content Delivery Network). The website uses a secure HTTPS connection with a valid SSL certificate issued by Amazon (DV type). The connection is encrypted using TLS 1.3 with the TLS_AES_128_GCM_SHA256 cipher suite and sha256WithRSAEncryption signature algorithm. The certificate covers 8 domain(s) (Subject Alternative Names) and expires on 2026-10-16, which is 102 days from now. The security headers analysis reveals a score of 0/100 (poor). No security headers are configured, which is a significant security concern. However, the site is missing Content-Security-Policy, Strict-Transport-Security (HSTS), 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 6 technologies across 5 categories powering class101.net. The detected stack includes Next.js css, React, Webpack, Vite, reCAPTCHA v3, and Fastly. The site uses Next.js as its primary framework (version css). The UI is built with React. Based on our comprehensive analysis of domain age, SSL configuration, email authentication, security headers, and blacklist status, class101.net receives an overall trust score of 66/100, classified as "Likely Safe".

After conducting a thorough safety and legitimacy analysis, class101.net receives a trust score of 66/100, 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, a valid SSL certificate issued by Amazon with 102 days until expiration, SPF (Sender Policy Framework) email authentication preventing email spoofing, and DMARC email authentication with a quarantine policy. 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 class101.net 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 class101.net and identified 6 distinct technologies across 5 categories. This analysis is performed by examining HTTP response headers, HTML source code patterns, JavaScript library fingerprints, CSS framework signatures, and DNS records. Framework: Next.js (version css) — provides the application framework and routing for class101.net. UI Library: React — handles the user interface rendering and component management for class101.net. Build Tool: Webpack and Vite — bundles and optimizes the JavaScript and CSS assets for class101.net. Security: reCAPTCHA v3 — provides security features like bot detection and CAPTCHA for class101.net. CDN: Fastly — accelerates content delivery by caching assets at edge locations worldwide for class101.net.

class101.net delivers its homepage in 17855ms (server response time), which is considered slow by industry standards. The total page weight is 982 KB, and we detected 63 resource requests loading assets from 6 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 class101.net. 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: 1 out of 2 CSS files and 1 out of 24 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. The site is served through a Content Delivery Network (CDN), which caches static assets at edge servers around the world. This means visitors from different geographic regions receive content from the nearest edge server, significantly reducing latency. CDN usage is particularly important for websites with a global audience, as it can reduce page load times by 40-60% for distant visitors. From an environmental perspective, each page view of class101.net produces approximately 0.48g of CO₂, earning a carbon rating of D. The website's carbon footprint could be reduced by optimizing images, enabling compression, reducing third-party scripts, and leveraging caching. For reference, the average web page produces about 0.5g of CO₂ per page view. The page weight of 982 KB is the primary factor in this calculation. Core Web Vitals data from the Chrome User Experience Report (CrUX) is not available for class101.net. 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.

class101.net resolves to the IPv4 address 13.33.235.113, 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 4 A record(s) configured. The domain name system is managed by 4 name servers: ns-1146.awsdns-15.org, ns-1798.awsdns-32.co.uk, ns-49.awsdns-06.com, and ns-648.awsdns-17.net. Having 4 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 class101.net is handled by Google Workspace with 5 MX records configured: aspmx.l.google.com, alt1.aspmx.l.google.com, and alt2.aspmx.l.google.com and 2 more. 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 quarantine policy — a moderate setting, directing unauthorized emails to spam/junk folders. 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 class101.net. 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 class101.net contains 49 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 0 H2 headings, 0 H3 headings, 0 H4 headings. The page includes 2 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 5 internal links pointing to other pages on the same domain and 6 external links pointing to third-party websites. There are 24 external JavaScript files, 2 CSS stylesheets, and 0 iframes on the page. The site implements the following web standards and features: robots.txt (controls search engine crawling behavior), Schema.org structured data (Organization, WebPage, and WebSite), and Progressive Web App (PWA) manifest (enabling app-like installation). Notable missing features: XML Sitemap. Adding these could improve search engine discoverability and rich result eligibility. We detected the following payment methods accepted on class101.net: Discover, JCB, and Afterpay. 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 (@Class101Korea), Instagram (@class101_official), and Youtube (@UCDJ1ZXSnt37KLaLFPFlBkqw). An active social media presence is a positive trust indicator and helps build brand awareness and customer engagement.

The title tag for class101.net is well-optimized at 46 characters: "CLASS101+ | Learn New Hobbies or Skills Online". The length falls within the ideal range for Google search results, ensuring the full title is displayed without truncation. The meta description is 100 characters (well-optimized): "South Korea’s #1 online class platform. 6500+ classes. Digital drawing, illustration, crafts & more.". 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://class101.net/en, preventing duplicate content issues, the page language is declared as en, the meta robots directive is set to all, and a favicon is configured. Open Graph meta tags are configured with 4/4 recommended fields: OG title ("CLASS101+ | Learn New Hobbies or Skills Online..."), OG description, OG image (social sharing thumbnail), OG type (website). These tags control how the page appears when shared on Facebook, LinkedIn, and other social media platforms that support the Open Graph protocol. The site implements Schema.org structured data with the following types: Organization, WebPage, and WebSite. Structured data helps search engines understand the page content and can enable rich results (featured snippets, knowledge panels, star ratings) in Google search results, which can significantly increase click-through rates.