Website tools
DNS records
A and AAAA records point to website addresses. CNAME records name an alias, MX directs incoming mail, and TXT carries text such as verification tokens. TTL is the remaining cache lifetime reported by the resolver, in seconds.
A lookup is one public resolver's observation, not proof of worldwide propagation. DNS checks use Cloudflare's public resolver. They do not change your records.
Email DNS
Use your mail provider's exact MX and authentication values. Keep one SPF policy per name; combine authorized senders in that policy rather than publishing a second one. DKIM selectors come from the mail provider, not from the domain name.
Record discovery does not test a mailbox or validate a message signature. Sources: SPF, DMARC, Null MX. Lookups use Cloudflare's public DNS resolver.
Certificate dates
A website presents its TLS certificate when a secure connection starts. Renew it before its expiry date and confirm that the renewed certificate is installed. Different servers behind the same hostname can present different certificates.
This expiry-only check inspects one public address on port 443. It does not verify the certificate authority, hostname match or website safety, and it does not fetch website content.