Domain Availability Checker

Server assisted New DNS & Domains

For each name the Mutqan server asks the registry's RDAP service for a record and Cloudflare's public resolver for the name's NS delegation. A record or a delegation means the name is registered; "likely available" is shown only when the registry answers "not found" and DNS answers NXDOMAIN. Reserved, blocked and premium names look the same as free ones from outside, so a registrar's search has the final word. Under a registry without RDAP, such as .sa, only a name delegated in DNS can be called registered; any other answer is reported as not checkable here.

Privacy: The domain, address or URL you enter is sent from the Mutqan server to the public data service named on this page (a registry, a resolver, a certificate log or a measurement network). Nothing is stored.

How can you tell whether a domain name is available?

Only the registry, through a registrar, can say for certain that a name can be registered and at what price. From outside, two public signals help: the registry's RDAP service has no record of the name (HTTP 404), and DNS has no delegation for it (NXDOMAIN). When both agree the name is probably free, but reserved, blocked and premium names give the same answers, so a registrar's search has the final word.

How to use Domain Availability Checker

  1. Enter up to five domain names, one per line.
  2. Press Check availability.
  3. Read the Verdict column with the two signals beside it: a registry record or a DNS delegation means the name is taken.
  4. For a name marked "Likely available", search for it at a registrar of your choice: only the registrar can confirm it can be registered and quote the price.

Domain Availability Checker features

  • Up to five names per run, one per line, each reduced to the name a registry would actually sell
  • Two independent signals per name: the registry's RDAP record and the NS delegation in public DNS
  • "Likely available" only when the registry says "not found" and DNS says the name does not exist; anything less is "Unknown"
  • A clear "Not checkable here" for names under registries without RDAP that DNS cannot settle, with a link to the top-level domain's IANA page
  • One plain sentence per name explaining what the two signals mean together
  • No registration offers and no registrar links: the names go only to the registry and a DNS resolver

Inputs and outputs

Inputs

  • Domain names: one to five names, one per line (commas and spaces also separate them). Hosts such as shop.example.co.uk are checked as their registrable name.
  • Pasted URLs are reduced to their host name; IP addresses and names without a dot are listed as invalid instead of being sent.

Outputs

  • Summary: names checked, then how many of them are already registered, likely available, or unknown or not checkable (failed checks and misspelled top-level domains count as not checkable, so the three add up to the first).
  • Results: per name the name actually checked, the verdict, the registry signal (record found, no record, no RDAP service, no answer) and the DNS signal (delegated, NXDOMAIN, no clear answer).
  • What the signals mean: one sentence per name, plus any detail the registry or the resolver reported.
  • Before you register: what "likely available" can and cannot tell you.

Domain Availability Checker example

One registered name and one unused name

Input:

wikipedia.org
mutqan-sample-name-7f3k.com

Output:

Summary: Names checked 2 · Already registered 1 · Likely available 1 (confirm with a registrar) · Unknown or not checkable 0
Results:
wikipedia.org | wikipedia.org | Already registered | Record found | Delegated (NS records)
mutqan-sample-name-7f3k.com | mutqan-sample-name-7f3k.com | Likely available | No record (404) | Does not exist (NXDOMAIN)
What the signals mean: mutqan-sample-name-7f3k.com: no registry record and no DNS delegation. Reserved, blocked and premium names look the same from outside, so only a registrar's search can confirm that it can be registered, and at what price.

How to read the Domain Availability Checker results

Already registered: the registry holds a record, or the name is delegated in DNS. Use WHOIS / RDAP Lookup to see the registrar and the expiry date.

Likely available: no registry record and NXDOMAIN in DNS. Reserved, blocked and premium names give the same result, so this is a strong hint, not a promise.

Unknown: the two signals do not agree or one of them failed. Nothing can be concluded; try again shortly or search at a registrar.

Not checkable here: the registry publishes no RDAP service and DNS shows no delegation. The top-level domain's entry in IANA's root zone database names the registry, whose own website can answer the question.

Not a top-level domain: the root zone has no such top-level domain, usually a typo such as .con for .com, so no name under it can be registered. Correct the name and check again.

When to use Domain Availability Checker

  • Shortlisting names for a new product or company before going to a registrar.
  • Checking a few spelling variants or other top-level domains of a brand at once.
  • Confirming that a lapsed name has really been released before trying to register it.

Troubleshooting

  • "Not checked": the per-minute limit on registry queries was reached during the run. Wait a minute and check those names again.
  • "Unknown", or "Already registered" with a note that the registry did not answer: one side failed or was rate-limited. Run the check again a little later.
  • A message that the name is a public suffix: names such as co.uk or com.sa belong to the registry itself; check a name under them, such as example.co.uk.
  • "Invalid name": the line is an IP address, has spaces or characters a domain cannot have, or has no dot.

Frequently asked questions about Domain Availability Checker

Can I register a name marked "likely available"?

Probably, but not certainly. The registry has no record and DNS has no delegation, which is also true of reserved names, names a registry blocks and premium names sold at a higher price. Search for it at a registrar: only the registrar can say whether it can be registered and what it costs. Mutqan does not register domains.

Why is a .sa name "not checkable here"?

The .sa registry publishes no RDAP service, so it cannot be asked. A .sa name delegated in DNS is still shown as registered, because only a registered name can be delegated; for any other .sa name the tool will not guess from DNS alone. It says so and links to the top-level domain's page at IANA, which names the registry and its website.

Why does a name with no website show as registered?

Registration and hosting are separate. A name can be registered with nameservers and no website, or registered and parked. The check reads the registry record and the DNS delegation; it does not open any website.

Does checking a name tell anyone I am interested in it?

The name goes from the Mutqan server to the registry's RDAP service and to Cloudflare's public DNS resolver, and to no registrar; Mutqan stores nothing. The registry and the resolver see a query from Mutqan's server, as with any lookup, not from your connection.

Why was shop.example.co.uk checked as example.co.uk?

Only a registrable name can be registered. The server reduces what you enter with the ICANN section of the Public Suffix List and checks the name a registry would actually sell.

Technical notes

The registry signal is an RDAP domain query (RFC 9082) at the server listed for the top-level domain in IANA's bootstrap registry (RFC 9224); RDAP answers a name it holds no object for with 404 Not Found (RFC 7480 §5.3). The DNS signal is an NS query for the same name through Cloudflare's public resolver: a delegation (NOERROR with NS records) exists only for a registered name, and NXDOMAIN means the parent zone has no such name.

The two are combined conservatively: a record or a delegation gives "registered"; "likely available" needs both a 404 and NXDOMAIN; a top-level domain missing from the bootstrap registry gives "unsupported" unless DNS already shows a delegation, or "not a top-level domain" when the root zone answers NXDOMAIN for the top-level domain itself (a typo such as .con); every other mix (a registry error, a resolver failure, a name that exists in DNS without its own delegation) gives "unknown". WHOIS is never used for this verdict.

Limitations and methodology

From outside a registry, a reserved, blocked or premium name looks the same as a free one; only a registrar's search knows the difference and the price.

The answer is true at the moment of the check. A name can be registered by someone else a minute later, and nothing here reserves it.

Under registries without RDAP only a delegated name can be identified (as registered); WHOIS formats differ too much to read availability from them reliably, so the rest are not checkable here.

Security and privacy

Each name goes from the Mutqan server to its registry's RDAP service and to Cloudflare's public DNS resolver, and to no registrar. Nothing is stored; analytics record only that the availability endpoint was used.

References