Free Security & DNS Tools
Check DNS, email authentication, TLS, headers, redirects, and browser security policies without installing specialist software.
DNS Lookup Tool
Inspect A, AAAA, MX, TXT, NS and CNAME records.
Open tool →DNS Propagation Checker
Check DNS visibility across multiple resolvers.
Open tool →MX Lookup Tool
Inspect mail routing records for a domain.
Open tool →SPF Checker
Validate SPF records and surface common issues.
Open tool →DKIM Checker
Query and inspect DKIM records by selector.
Open tool →DMARC Checker
Validate DMARC policy and reporting settings.
Open tool →CAA Checker
Check which certificate authorities are authorised for a domain.
Open tool →SSL Certificate Checker
Inspect certificate details and validity.
Open tool →Security Headers Checker
Review key HTTP security headers.
Open tool →CSP Checker
Parse and inspect Content Security Policy directives.
Open tool →CORS Checker
Test cross-origin request configuration.
Open tool →HTTPS Redirect Checker
Verify HTTP traffic is redirected to HTTPS correctly.
Open tool →Free security tools without the clutter
These tools help developers and site owners validate the configuration that sits around a website: DNS, certificates, email authentication and security headers. Use them for quick diagnostics and configuration checks.
SiteTidy keeps each tool focused on one job, with direct links between related utilities so you can move from diagnosis to remediation without hunting through multiple sites.