51.com

We performed a comprehensive analysis of 51.com on 2026-07-06. The website returned an HTTP 200 status code with a server response time of 14700ms. The page is served over HTTP/1.1 protocol with Gzip compression enabled, achieving approximately 60.0% size reduction. The total page weight is 112 KB. The website uses a secure HTTPS connection with a valid SSL certificate issued by DigiCert Inc (OV type). The connection is encrypted using TLS 1.2 with the ECDHE-RSA-AES128-GCM-SHA256 cipher suite and sha256WithRSAEncryption signature algorithm. The certificate covers 2 domain(s) (Subject Alternative Names) and expires on 2027-01-08, which is 186 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 1 technologies across 1 categories powering 51.com. The detected stack includes jQuery. Based on our comprehensive analysis of domain age, SSL configuration, email authentication, security headers, and blacklist status, 51.com receives an overall trust score of 60/100, classified as "Likely Safe".

After conducting a thorough safety and legitimacy analysis, 51.com receives a trust score of 60/100, 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 and a valid SSL certificate issued by DigiCert Inc with 186 days until expiration. 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 51.com 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 51.com 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 — provides utility functions and DOM manipulation for 51.com.

51.com delivers its homepage in 14700ms (server response time), which is considered slow by industry standards. The total page weight is 112 KB, and we detected 376 resource requests loading assets from 19 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: 1 out of 14 CSS files and 2 out of 9 JavaScript files are minified. Minifying the remaining 20 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 51.com 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 112 KB is the primary factor in this calculation. Core Web Vitals data from the Chrome User Experience Report (CrUX) is not available for 51.com. 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.

51.com resolves to the IPv4 address 122.188.45.51, 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 13 A record(s) configured. 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 51.com. 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 51.com contains 414 words of visible text content. This is a moderate amount of content. The page is structured with 0 H2 headings, 6 H3 headings, 0 H4 headings. The page includes 68 images. 58 images (85%) are missing alt text attributes, which is a significant concern for both accessibility and SEO. Screen readers rely on alt text to describe images to visually impaired users, and search engines use alt text to understand image content. Only 15% of images have proper alt text — we recommend adding descriptive alt attributes to all images. The link structure consists of 38 internal links pointing to other pages on the same domain and 215 external links pointing to third-party websites. There are 9 external JavaScript files, 14 CSS stylesheets, and 0 iframes on the page. The site implements the following web standards and features: robots.txt (controls search engine crawling behavior). Notable missing features: XML Sitemap and Schema.org structured data. Adding these could improve search engine discoverability and rich result eligibility.

The title tag for 51.com is well-optimized at 42 characters: "五一网|51游戏_好玩的游戏社区化平台_51游戏官网|51页游|空间尽在51.com". The length falls within the ideal range for Google search results, ensuring the full title is displayed without truncation. The meta description is 121 characters (well-optimized): "玩游戏,上51.COM。51游戏平台是国内知名的专业游戏社区化平台,在这里玩家们可以尽情体验畅玩游戏、讨论游戏、共创游戏的快乐。创立20多年来，51游戏已集游戏研发、游戏运营为一体,不断为玩家提供高品质、好玩的游戏产品,为玩家提供真诚的服务...". 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. A favicon is configured. Open Graph meta tags are configured with 4/4 recommended fields: OG title ("51|51游戏_好玩的游戏社区化平台_游戏|交友|空间尽在51.com..."), OG description, OG image (social sharing thumbnail), OG type (article). 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 51.com, 51, 51游戏, 51个人空间, and 51页游. 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.