Find a domain's IP addressesFind the servers a domain points at - the addresses a browser would connect to. Use it to check a site is pointed where you expect after a move, to confirm a customer's domain has gone live, or to find out whether a domain exists at all. Both modern and older address types are looked up together.
Find a domain's mail serversFind out who handles a domain's email, and whether it can receive any at all. The servers come back in the order mail is offered to them, so the first one is the one that normally takes it. Use it to check an address is worth sending to before a campaign, to see which provider a company's mail runs through, or to confirm a mail migration has finished.
Find a domain's text recordsRead the notes a domain's owner has published on it. This is where verification codes live: when a service asks a customer to 'add this record to prove you own the domain', this is where it lands. Give it the code you are waiting for and the step tells you whether it has appeared yet, so a workflow can check every hour and carry on the moment it does.
Check a domain's email securityFind out whether a domain is set up to stop other people sending email that appears to come from it. Three records have to agree for that to work, and this reads all three and says what they add up to in a sentence, with a list of anything missing. Use it to audit your own domains, to check a client's before taking on their email, or to score a prospect's security posture.
Find a domain's name serversFind out who runs a domain's DNS - the servers that answer every question about it. The names give away the provider, so this is how you tell that a domain is on Cloudflare, or Route 53, or still with the registrar. Use it to confirm a domain transfer has taken effect, or to check a customer has pointed their domain at you before you go looking for the records.
Find a domain's aliasFind out whether a name is a signpost to somewhere else, and where it points. This is the check behind every 'point your domain at us' onboarding step: a customer is told to send support.their-company.com to your service, and this is how a workflow knows whether they have done it and finishes setting them up on its own.
Find the host name for an IP addressTurn an IP address back into a name. A visitor's address on its own says nothing; its name often says who they are - a company, a cloud provider, a home connection. Use it to put a name on an address in a log, or to check that a server you run is named the way your mail provider expects. Works for both address styles.
Look up any DNS recordRead any kind of DNS record, for the questions the other steps do not cover: which authorities may issue certificates for a domain, where a service lives, when its records were last changed. Pick the kind of record from the list and the values come back as they were published.