DNS Lookup

All nine common ones in a single pass: A, AAAA, CNAME, MX, TXT, NS, SOA, SRV, and CAA. Each type gets its own section in the results, including an explicit note when a type returns nothing.

That depends on the TTL the old record carried. If it was 3600 seconds, resolvers can keep serving the stale answer for up to an hour after your change. Once caches expire, this tool reflects whatever your authoritative nameservers currently publish.

Because most domains genuinely don't have every type. SRV and CAA records are relatively rare, and a root domain usually won't have a CNAME at all. An empty section is information, not an error.

That's the priority value, and lower wins. A record like priority 10 for mx1.example.com and priority 20 for mx2.example.com tells sending servers to try mx1 first and fall back to mx2 if it's unreachable.

Yes, and you often should. CNAME records typically live on subdomains like www or shop, and verification TXT records frequently sit on prefixed names such as _dmarc.example.com. Query the exact hostname you care about.

The query runs server-side through Node's resolver at the moment you press Lookup, so it's live from that resolver's point of view. It can still differ briefly from what your ISP's resolver serves, since each resolver expires its cache on its own schedule.

The DNS protocol stores TXT data in strings of at most 255 characters, so a long DKIM key comes back as multiple pieces. Receiving software joins them back together, and you should too when comparing values.