Call the free Domain IP Lookup API endpoint
curl https://aisenseapi.com/services/v1/domain_ip_lookup/example.com{"domain":"example.com","ip":"104.20.23.154"}The hostname goes in the path. There is no query string, no request body and no header to set, so anything that can fetch a URL can use this.
Other names work the same way. A call for github.com returned {"domain":"github.com","ip":"140.82.121.4"}.
Response fields
| Field | Type | Description |
|---|---|---|
| domain | string | The hostname that was looked up, echoed back so a response can be matched to its request. |
| ip | string | The address this server's resolver returned for that hostname at the moment of the request. |
Two fields are the whole schema. A client that reads only ip keeps working even if the response gains keys later.
What the answer actually means
A DNS lookup is not a read from one global table. It is a question asked of one resolver, from one place, at one moment. All three of those change the answer, and this is where the result gets misread.
- Answers differ by resolver
Resolvers hold their own cached copies of a record and expire them on their own schedule. Two resolvers asked a second apart can return different addresses for the same name, and neither one is wrong.
- Answers differ by location
Large sites sit behind CDNs and anycast networks that deliberately return a nearby edge address. What you get here is the edge closest to this server, not an origin machine, and not what a visitor in another country would receive.
- Records change
An A record can be edited at any time. The change then spreads outward as caches expire, rather than switching everywhere at once.
The third point is easy to demonstrate with this endpoint alone. An earlier call for example.com returned 104.20.23.154. A later call for the same name returned 172.66.147.243. Nothing broke between them. The record simply moved, and the response is a snapshot rather than a permanent fact about the domain.
Why a second opinion is the point
Read that way, the endpoint earns its keep precisely because it answers from outside your network. Compare the address it returns with the address your own machine resolves, and a slow argument turns into a fast diagnosis.
Agreement means the change is live and your view of it is current. Disagreement is itself the finding, and it usually points at one of a short list of local culprits: a stale entry in an operating system or browser cache, a hosts-file line added months ago and forgotten, or a record you edited that has not reached your resolver yet.
That same logic makes the free Domain IP Lookup API endpoint useful inside automation. A deploy script can poll it through a propagation window and stop waiting the moment the new address appears. An agent with no shell, and therefore no dig and no nslookup, can still resolve a name over plain HTTP.
For the opposite direction, take an address and ask what is known about it with the IP Reverse Lookup API endpoint. To learn which public address your own requests arrive from, call the Client IP API endpoint first, then resolve the hostname you expected it to match.
Common uses
Confirm a DNS change went live
Point a domain somewhere new, then poll from outside your own network to see when the record actually changed.
Verify a migration
After moving a site or a service, check that the hostname now resolves to the new host rather than the retired one.
Catch a stale local cache
When a site loads wrongly only for you, compare this answer with your machine's. Seconds later you know whether the fault is local.
Allowlist an address
Resolve a partner hostname to the address a firewall rule or a security group needs.
Resolution without a shell
Let an agent or a browser-based tool resolve a hostname over HTTP when it has no access to command line tools.
Privacy and limits
The hostname appears in the request path, so it is visible in ordinary request logs. Treat internal hostnames the same way you would treat any other value you put in a URL.
No account and no API key. The service-wide limit is 5000 requests per IP per 24 hours, which is ample for watching a record through a propagation window as long as you leave a sensible gap between checks.
Every service in the family shares that limit and the same base URL, https://aisenseapi.com/services/v1. To check that a host answers at all before you resolve it, use the Ping API endpoint, and watch the service itself with the Health Check API endpoint. The full catalogue lives on the free public REST APIs hub.