Spamhaus provides a free reputation checker that lets you verify if an IP address or domain is listed on their blocklists. It’s a trusted resource for diagnosing email delivery issues and identifying malicious activity.

🔍 Check IP addresses and domain names against Spamhaus blocklists

📧 Diagnose email delivery problems caused by poor sender reputation

🛡️ Identify malicious domains, compromised servers, or spam sources

⚡ Fast, reliable, and widely used by ISPs and mail providers

🌐 Web‑based tool, no installation required

🤝 Maintained by the Spamhaus Project, a global authority on spam and cyber threats

Perfect for: Sysadmins, email service providers, and security‑conscious users who need to verify sender reputation.

Afraid.org (FreeDNS) offers free DNS hosting and dynamic DNS services, making it easy to manage domains and subdomains without cost. It’s widely used for personal projects, small businesses, and privacy‑conscious users.

🔧 Free DNS hosting for domains and subdomains

⚡ Dynamic DNS support for devices with changing IP addresses

📂 Static DNS hosting and domain forwarding options

🌍 Large community with thousands of shared domains available

🖥️ Simple web interface for easy setup and management

🤝 Trusted by hobbyists, developers, and small organizations worldwide

Perfect for: Users who want reliable, free DNS hosting and dynamic DNS services without vendor lock‑in.