Look up any domain
Whether a domain is registered and which DNS records it has, free with no key. A paid plan answers the records themselves with when we last saw each, the address ranges its organization holds, and whether it's a disposable email domain.
Registration and which records a domain has are free, with a key or without one. The records, the ranges and the disposable flag are on every paid plan. A free account's first 100 lookups each day answer every field.
What people use it for
Sign-up checks
Refuse an email address whose domain has no mail server, or one from a disposable email service.
Vendor and partner checks
The address ranges an organization holds, from the domain it gives you.
Phishing triage
A suspicious name's records, and the networks its addresses sit on, in one lookup each.
Attack surface
An organization's address ranges and the AS that announces them, to scope what to watch.
What the answer says
Free fields answer with a key or without one, with no cap. Paid ones come with every paid plan, and a field your plan doesn't include is left out of the answer, never sent as false.
Every field, plan by plan, is on Pricing, and each one is described in the documentation.
- is_registered
- Whether the domain is registeredFree
- has_a, has_aaaa, has_mx
- Which records it has, as has_ns and has_cnameFree
- dns
- Its A, AAAA, MX, NS and CNAME records, with when we last saw eachPaid
- ip_ranges
- The address ranges the domain's organization holdsPaid
- is_disposable
- A disposable email domain, with the services behind itPaid
Check an email's domain
The same API answers an address, an AS (AS15169) or a domain; only the path changes.
There are SDKs for 12 languages, a CLI and an MCP server. The API has the endpoints and limits.
import { InternetData } from "@internetdata/internetdata";const client = new InternetData({apiKey: process.env.INTERNETDATA_API_KEY,});const d = await client.lookupDomain(email.split("@")[1]);if (!d.hasMx || d.isDisposable) {return refuseSignup();}
Look one up now.
Unlimited answers with no key and no cap, and a free account's first 100 lookups each day answer every field.