Free tools
SignNexa ships a set of free diagnostic tools. They need no account and no sign-up - you enter a domain and get a result. This guide explains what each one checks so you know which to reach for, and how to read what comes back.
Start here if you are not sure
Run Quick Scan from the tools hub. It looks at a domain broadly and points you at whichever area needs attention, so you can go straight to the specialist tool for it rather than guessing.
Intelligence - understand a domain
- Domain Intelligence
- WHOIS and registration details: registrar, creation and expiry dates, and domain status flags. Use it to confirm who holds a domain and to catch an expiry creeping up on you.
- Email Intelligence
- SPF, DKIM, DMARC, mail routing, and blacklist checks for a domain. This is the one to run when mail is landing in spam.
- Website Intelligence
- HTTPS setup, security headers, the raw HTTP response, and the technologies a site runs on. Use it to spot missing security headers before someone else does.
- Inbox Tester
- Send a real email to the address it gives you and see the true SPF, DKIM, DMARC, and alignment results for that specific message. It tests what receivers actually see, not what your DNS claims.
Infrastructure - what sits behind the domain
- SSL & TLS Inspector
- The certificate chain, subject alternative names, key, protocol, cipher, and expiry date. Run it when a browser warns about a certificate, or a few weeks before one is due to renew.
- DNS Explorer
- Every DNS record for a domain, plus DNSSEC, CAA, and nameservers. Useful for seeing the full picture when you have inherited a domain and do not know how it is configured.
- DNS Propagation
- Queries resolvers around the world to show how far a DNS change has spread. Run it after editing a record, before concluding the edit did not work.
Performance - how fast a page loads
Performance Snapshot reports Core Web Vitals and PageSpeed results for a page. Treat it as a lab snapshot: it is one measurement from one place, so use it to compare a page against itself over time rather than as an absolute verdict.
Signatures without an account
The Email Signature Generator lets you pick a template, add your details, and copy a finished signature without signing up. A SignNexa account adds the parts a one-off generator cannot: saving and editing signatures later, reusable profiles, and a Nexa Page to link to.
Fair use
The free tools are rate limited so everyone gets a turn. If you hit a limit, wait a little and try again - signing in raises the allowance on the checks that have a signed-in tier.
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