Website health
What can a domain or website checker actually prove?
Short answer: A checker can report what it observed at a particular time and location; it cannot certify security, inbox delivery or availability for every visitor.
The full answer
A DNS audit can show that an SPF or DMARC policy is published and that a queried DKIM selector returns a key. It does not establish that every sending service is configured correctly or that a real email will pass aligned authentication.
Website checks can provide evidence about a particular request. Network restrictions, caching, cross-origin browser rules and regional routing can change results. A successful request does not validate every page, payment flow or account action.
Treat unavailable results as unknown, not confirmed failures. Follow up with authoritative DNS checks, actual message headers, browser testing and hosting logs as appropriate. DomainGuard’s score is a heuristic aid, not a security certification.