WHOIS Lookup
Ask one WHOIS server for one name and read the reply from TCP port 43.
The query runs on your computer through the local agent. The name, the server and the reply stay on this page.
Local agent
Paste the current code from the agent window. The field is cleared after each attempt.
Agent disconnected
Set up the agent
Download and start the local agent, then come back to this page.
About the agent and download- Start MyDevTools Agent. A private or loopback address needs the agent started with --allow-private.
- Copy the pairing code from the agent window.
- Paste the code below. If the browser asks for local-network access, allow it for this connection.
The browser sends the query, the server and the timeout only to the agent on 127.0.0.1. The agent opens one TCP connection to port 43, sends one line, reads the reply and closes. It does not follow a referral to a second server. The check does not go to a MyDevTools server. This browser remembers the timeout. It does not store the query, the server or the reply.
Query
One name or handle, up to 255 characters. A second line, a URL and a numeric range are not a query. The agent sends this line once and does not follow a referral.
One WHOIS server host. The agent always uses TCP port 43. Private and loopback addresses need --allow-private.
How long to wait for this one query, from 200 to 10000 milliseconds.
Result
Check one name on one WHOIS server to see the reply.
- Address
- Time
The answer was cut after 64 KiB.
On this page
WHOIS Lookup asks the local agent to open one TCP connection to port 43 on a WHOIS server you name, send one line, and show the reply. The grant is whois.lookup, separate from http.request, icmp.trace, dns.lookup, tcp.connect and tls.inspect.
Detailed Functionality
The agent resolves the server to the first address and applies the same destination rules as TCP connect. Private and loopback addresses work only when the agent was started with --allow-private. The query is one line ending in a carriage return and a line feed. A URL, a second line and a numeric range such as 80-443 are rejected. The reply is kept up to 64 KiB and is not followed when it names another server. At most two queries run at once. The timeout stays in this browser. The name, the server and the reply do not.
Practical Examples
example.comonwhois.iana.orgshows the reply text, including a referral line when the registry sends one.127.0.0.1with nothing listening on port 43 shows a refusal.80-443is rejected. This is not a scan.
How to Use This Tool
Start the local agent
Download the agent, start it, and copy the pairing code.
Pair WHOIS
Paste the code and connect. The page asks for whois.lookup and keeps capabilities this browser already holds.
Query one name
Enter one name and one WHOIS server, set the timeout, and press Check.
Read the reply
The page shows the status, the address, the time and the text. Copy it. Reloading the page clears the name, the server and the reply.
Tips and Best Practices
- A refused connection, a timeout and an empty reply are results. They are not a failed check.
- One request is one name and one server on port 43. A referral inside the text is not followed.
- At most two queries run at once.
- The published Windows download may be older than this page. WHOIS needs an agent that advertises whois.lookup.