DNS

Explain, format, and generate DNS records, reverse zones, and PTR entries.

Build and validate a DNS CAA record for issue, issuewild, iodef, or an unknown property tag without checking certificate authorization.

Explain common DNS record types and inspect a pasted single-line DNS record locally.

Normalize a safe, single-line subset of pasted DNS zone-style records entirely in the browser.

Structurally parse pasted DS, DNSKEY, RRSIG, NSEC, and NSEC3 records and explain their fields without performing DNSSEC validation.

Parse pasted DNS MX records, sort their preferences, and identify a correctly formed Null MX record without performing DNS lookups.

Convert an IPv4 or IPv6 address to its reverse-DNS owner name and optionally format a PTR record.

Calculate traditional, RFC 2317 classless IPv4, and nibble-aligned IPv6 reverse-DNS zones from CIDR.

Generate and validate a DNS SRV record from service, protocol, priority, weight, port, and target fields.