Squish & Co. — diagnostics dept.
The Tool Shed
Complimentary diagnostics for domains, DNS, and email — no signup, runs right in your browser.
Tune-Up
One graded report for your whole domain — email, SSL, blocklists and headers.
DMARC Checker
Test a domain's DMARC, SPF, and DKIM records and see how to fix gaps.
DNS Checker
Look up A, AAAA, MX, TXT, CNAME, and NS records for any domain.
WHOIS Lookup
See registration, registrar, and expiry for any domain.
SSL Checker
Verify a site's TLS certificate, chain, and expiry.
Email Deliverability Test
Score a domain's email-auth setup end to end.
AI Visibility Check
Grade how legible your business is to ChatGPT, Perplexity, and Google AI — and see what's blocking them.
Hosting Checker
Find out who hosts any website — plus the CDN, DNS, and email behind it.
Blacklist Checker
Check a domain and its IP against 7 major spam and malware blocklists.
Is It Down?
Check whether a website is down for everyone or just you — status, response time, and redirects.
Security Headers Checker
Grade any site's HTTP security headers on what they actually do.
Website Technology Checker
See what any site is built with — CMS, framework, server, CDN and analytics.
Redirect Checker
Trace every hop a domain redirects through, and check HTTP upgrades to HTTPS.
Missing a tool?
Ask in the chat on squish.co — it runs every tool on this board for you, plus a few we haven’t hung up yet.