surbl.org

We performed a comprehensive analysis of surbl.org on 2026-06-29. The website returned an HTTP 200 status code with a server response time of 29709ms. The page is served over HTTP/2 protocol with Gzip compression enabled, achieving approximately 60.0% size reduction. The total page weight is 8 KB. The website uses a secure HTTPS connection with a valid SSL certificate issued by Sectigo Limited (OV type). The connection is encrypted using TLS 1.3 with the TLS_AES_256_GCM_SHA384 cipher suite and sha256WithRSAEncryption signature algorithm. The certificate covers 2 domain(s) (Subject Alternative Names) and expires on 2026-08-26, which is 58 days from now. The security headers analysis reveals a score of 85/100 (good). The following security headers are properly configured: Content-Security-Policy, Strict-Transport-Security (HSTS), X-Content-Type-Options, Referrer-Policy, and Permissions-Policy. However, the site is missing X-Frame-Options, which could expose the site and its users to cross-site scripting (XSS), clickjacking, and other web-based attacks. Based on our comprehensive analysis of domain age, SSL configuration, email authentication, security headers, and blacklist status, surbl.org receives an overall trust score of 82/100, classified as "Very Likely Safe".

After conducting a thorough safety and legitimacy analysis, surbl.org receives a trust score of 82/100, which places it in the "Very 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 Sectigo Limited with 58 days until expiration, SPF (Sender Policy Framework) email authentication preventing email spoofing, and DMARC email authentication with a reject policy — the strongest available setting. Areas of concern include: no X-Frame-Options header, which could allow the site to be embedded in malicious iframes (clickjacking), 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 surbl.org 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 automated technology detection scan was unable to identify specific technologies on surbl.org. This could indicate that the site uses server-side rendering without client-side technology fingerprints, employs aggressive code obfuscation, or uses custom-built solutions that don't match known technology signatures.

surbl.org delivers its homepage in 29709ms (server response time), which is considered slow by industry standards. The total page weight is 8 KB, and we detected 33 resource requests loading assets from 0 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 1 CSS files and 0 out of 0 JavaScript files are minified. Minifying the remaining 1 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 surbl.org produces approximately 0.0g 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 8 KB is the primary factor in this calculation. Core Web Vitals data from the Chrome User Experience Report (CrUX) is not available for surbl.org. 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.

surbl.org resolves to the IPv4 address 5.161.67.209 and also supports IPv6 (2a01:4f8:1c1e:9792::1), demonstrating modern network infrastructure readiness. The domain has 3 A record(s) configured. The domain name system is managed by 6 name servers: blue.surbl.org, green.surbl.org, ns200.surbl.org, ns201.surbl.org, orange.surbl.org, and purple.surbl.org. Having 6 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 surbl.org is handled by prolocation.nl with 3 MX records configured: vmx01.prolocation.nl, vmx02.prolocation.nl, and vmx03.prolocation.net. 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 reject policy — the strongest setting, instructing receiving servers to reject unauthorized emails entirely. 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 surbl.org. 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 surbl.org contains 748 words of visible text content. This is a moderate amount of content. The page is structured with 7 H2 headings, 0 H3 headings, 4 H4 headings, 0 H5, and 1 H6 headings. The link structure consists of 29 internal links pointing to other pages on the same domain and 0 external links pointing to third-party websites. There are 0 external JavaScript files, 1 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 title tag for surbl.org is good at 5 characters: "SURBL". The length is acceptable, though it may be slightly truncated in some search result displays. The meta description is 10 characters (acceptable): "surbl desc". 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. No Open Graph tags are configured. When someone shares a link to surbl.org 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 1 terms including surbl keywords. 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.