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Domain Availability Checker

Check a domain name across major TLDs against authoritative RDAP servers — a missing record means likely available. TLDs without RDAP fall back to a DNS heuristic. Always confirm with a registrar before purchasing. Uses cloud-based processing.

Cloud AI Browser Native

How to Use the Domain Availability Checker

1. Type the name

Without extension first — TLD coverage is checked across majors.

2. Read the heuristic per TLD

Likely-registered or likely-available per extension — a DNS miss is not proof of availability, and premium/registrar status is not checked.

3. Register the winner

Claim available names at any registrar before someone else does.

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Frequently Asked Questions

Which TLDs does it check?

Major TLDs including .com, .net, .org, .io, .dev, .co, .app, and more. The checker queries DNS records to determine if a domain is registered or available.

How accurate are the results?

RDAP answers are authoritative: a record means registered, a missing record means likely available (premium/reserved names can still surprise you). Where a TLD has no RDAP, the tool falls back to DNS queries — weaker signal. Always verify with a registrar before purchasing.

Can I check multiple domains at once?

Yes. Enter a base name and the tool checks it across all supported TLDs simultaneously, showing availability status for each extension in a single table.

Does it suggest alternative names?

Yes — after a check, one click tests 6 variants (get-, -hq, -app, try-, -ly, the-) on .com through the same RDAP-first pipeline. Listed alternatives are checked verdicts, not guesses.

Is the lookup data stored?

We store no search history. But the checks themselves are DNS-over-HTTPS queries to Google's public DNS resolver, so queried names are visible to that third party — same as any DNS lookup.

Exactly which TLDs are checked, and how?

All 10 in one run: .com, .net, .org, .io, .dev, .app, .co, .me, .tools, .xyz — RDAP first per name, falling back to DNS A plus MX lookups (a mail-only domain still counts as registered). Each lookup is capped at 10 seconds.

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Look up domain registration information using public RDAP APIs. Check registrar, expiration date, name servers, and more.

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Last updated October 2026