How do you check if a domain name is available?
Ask DNS whether the name has name servers: if it has, someone owns it. If it has none, ask the registry of its ending for its record over RDAP: no record means nobody has registered it.
This page does both for every name and ending you give it. DNS answers in a few milliseconds, so hundreds of names are sorted in seconds and most taken ones drop out at once. Only the names DNS calls free go on to the registry, at the pace each registry allows, so the slow part is spent on the names worth knowing about.
What the results mean
| Free | The registry has no record of the name. You can most likely register it. |
|---|---|
| Likely | No DNS, and the ending's registry offers no lookup a browser can ask. Confirm with WHOIS before you count on it. |
| Taken | It has name servers, or the registry has a record of it (some registered names are parked without DNS). |
| Unclear | No answer could be trusted: the registry refused the name or did not answer. It is asked again next time. |
Which endings are confirmed by the registry?
Every ending whose registry runs RDAP, which is every generic ending (.com, .net, .org, .ai, .app, .dev, .xyz, .tech, .store, .shop, .online and the rest) and many country endings (.uk, .fr, .nl, .ca, .au). Country endings without RDAP, such as .io, .co, .me, .de, .eu, .se and .us, are checked by DNS only and shown as likely when free.
Google's registry (.app, .dev) and SIDN (.nl) answer only a few questions at a time, so names in those endings are confirmed more slowly; their DNS answer shows straight away.
Questions
Each name goes to Cloudflare's public DNS resolver, and the free ones to their registry. No registrar is asked, so no seller sees your ideas until you open their search yourself. Your list stays in this browser.
Registries set premium prices on short and common names and keep some names back. Neither DNS nor RDAP says so; the registrar's search shows the price.
500 names and up to 2,000 domains are checked at a time. Results are kept in this browser for a while, so the next batch only asks about the new names.