Free network diagnostic and security assessment tools. Check DNS, SSL certificates, email authentication, and more — no signup required.
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Aegis Digital Defense gives small businesses protection without the price tag. Fractional CISO + 24/7 MDR + endpoint detection. Based in Oklahoma, serving nationwide.
Look up DNS records for any domain. View A, AAAA, MX, TXT, CNAME, NS, SOA, SRV, and CAA records instantly.
Use ToolView domain registration details including registrar, creation date, expiration date, nameservers, and status.
Use ToolDiscover all subdomains for any domain using Certificate Transparency logs and other sources. Essential for attack surface discovery.
Use ToolBenchmark DNS resolver performance by measuring latency, reliability, and response times. Find the fastest DNS resolvers.
Use ToolCheck SSL certificate details including issuer, validity dates, expiration status, and security configuration.
Use ToolDeep SSL certificate analysis including key strength, signature algorithms, expiration, and security best practices.
Use ToolGet an A+ to F letter grade for your website's SSL/TLS configuration. Analyzes protocol versions, key strength, cipher suites, certificate validity, and known vulnerabilities.
Use ToolView and analyze email authentication records (SPF, DKIM, DMARC) for any domain. Prevent email spoofing and phishing.
Use ToolDeep SPF record analysis — enumerate authorized senders, detect configuration errors, validate DNS lookup count limits, and identify weaknesses that cause delivery failures.
Use ToolDiscover all active DKIM selectors on your domain. Validates cryptographic parameters, detects weak keys below 2048-bit, and provides setup guidance for major platforms.
Use ToolAnalyze DMARC policy configuration, identify issues, and get recommendations to improve email authentication.
Use ToolGet a comprehensive email security health score for your domain — SPF, DKIM, DMARC, and BIMI analyzed together with an overall grade and remediation roadmap.
Use ToolAegis Digital Defense gives small businesses Fortune 500-level protection without the price tag. Aegis-grade endpoint detection, email security, mobile management, incident response, and compliance consulting.
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