Domain Availability Checker

Check domain availability in bulk with a single click. Give it a list of full domain names and it returns a clean table showing whether each one is available for registration, which registrar holds it if taken, and how the result was determined.

No sign-ups, no API keys, no third-party services required. Paste your domains, click Start, and download your results.

---

Features

• RDAP-first, WHOIS-fallback lookups — uses the modern, structured RDAP protocol first, with a WHOIS fallback for the handful of TLDs that don't support it yet.
• 100+ TLDs supported out of the box, with automatic IANA lookup for anything unrecognized.
• Registrar detection — when a domain is taken, the registrar name is returned where publicly disclosed.
• Bulk-friendly — built and tuned for batches of 100-500 domains at a time: resource-aware concurrency, batched dataset writes, and a shared keep-alive connection pool keep runs fast without spiking CPU or memory.
• Transparent method reporting — every result shows exactly how availability was determined (rdap-direct, rdap-bootstrap, whois, or dns-fallback), so you can judge confidence at a glance.
• Budget-aware — respects your configured spend limit and stops cleanly when it's reached.
• No bare-name guessing — domains without a TLD are flagged as an error rather than silently expanded into .com/.io/etc., so results never reflect an assumption you didn't make.

---

Use Cases

Brand & Naming Check whether a shortlist of brand or product names is still available before you commit.

Domain Portfolio Monitoring Track domains you're watching and get notified (via your own scheduling) the moment one frees up.

Due Diligence Verify availability before recommending a name to a client or building a launch plan around it.

Bulk Audit Check hundreds or thousands of domains in a single run. Export as CSV, JSON, or Excel and drop it straight into your workflow.

---

Input

UI

Field	Type	Required	Description
Domain Names / URLs (domains)	List of strings	Yes	One or more full domains or URLs to check. Must include a TLD (e.g. mystartup.com) — bare names are not expanded. Full URLs, protocols, www., paths, and query strings are stripped automatically.
Proxy Configuration (proxyConfiguration)	Proxy editor	No	Proxy settings for RDAP lookups. Residential proxies (default) reduce blocking. WHOIS lookups (TCP port 43) are unaffected by proxy settings.

JSON

{
  "domains": [
    "example.com",
    "https://www.google.com",
    "openai.org",
    "my-startup.co.uk"
  ],
  "proxyConfiguration": {
    "useApifyProxy": true,
    "apifyProxyGroups": ["RESIDENTIAL"]
  }
}

---

Output

UI

Results appear as a table in the Apify Console with one row per domain:

Column	Description
Domain Name	The normalized domain (protocol, www, and paths stripped)
Available	Yes, No, or Unknown (if the lookup was inconclusive)
Status	success or error: <reason>
Method	How availability was determined: rdap-direct, rdap-bootstrap, whois, or dns-fallback
Registrar	Registrar name if taken and disclosed, otherwise N/A

Exportable directly from the Console as CSV, JSON, or Excel.

JSON

[
  {
    "domainName": "example.com",
    "available": "No",
    "status": "success",
    "method": "rdap-direct",
    "registrar": "MarkMonitor Inc."
  },
  {
    "domainName": "some-definitely-unregistered-name-12345.com",
    "available": "Yes",
    "status": "success",
    "method": "rdap-direct",
    "registrar": "N/A"
  },
  {
    "domainName": "mystartup",
    "available": "Unknown",
    "status": "error: missing TLD (bare names are not auto-expanded)",
    "method": "none",
    "registrar": "N/A"
  }
]

---

Support

Need help or want a feature added?

Contact Support — Fill out this quick form

We respond quickly and are happy to add TLD support, new output fields, or custom integrations.

---

Built with care by One Scales Inc.

---

domain availability domain checker domain lookup domain whois rdap dns lookup domain-availability domain-checker bulk brand-check domain-registration domain-lookup tld due-diligence