IP Address Lookup: What It Reveals & How to Check and Interpret Results

When you open a website, the page sometimes switches language on its own or serves content for a different region. That behavior can be tied to your public IP address. Sites typically use your IP to estimate roughly where you're connecting from, then combine it with signals like browser language to decide what to show you.

So what can an IP address lookup actually tell you? And beyond location and ISP, how should you read the results of DNS and WebRTC tests?

1. IP address lookup: what can it actually show?

An IP address is the network address your device uses to connect to the internet. Public registration records and IP geolocation databases let you look up the following:

•  IP location: usually the country, region, and city — but these results are estimates, and city-level detail can be off.

•  ISP or network holder: a telecom carrier, cloud provider, or corporate network, for example.

•  ASN (Autonomous System Number): identifies the network organization the IP belongs to, which helps you understand where the connection comes from.

•  IP block: the network range the address sits in. Some registration records also include allocation or update dates.

•  Network type: some databases classify addresses as residential broadband, mobile, or data center.

One thing worth keeping straight: IP registration data and geolocation data are not the same. The first reflects how address resources are allocated; the second is an inference drawn from various data sources.

A public IP lookup on its own usually can't tell you someone's name, home address, or street number.

2. Common ways to check your IP

To see the public IP your device presents to the outside world, you can use an online tool or the command line.

Option 1: use an online IP lookup tool

Open the IP detection page — no software required — and you can usually see your public IP, location, ISP, and ASN.

ToDetect, for example, also lets you look at DNS, WebRTC, and browser environment details, depending on what the page offers. Compared with checking a single IP, viewing several results side by side makes it easier to spot something off in your network configuration.

Option 2: check from the command line

On Windows, macOS, or Linux, open a terminal that supports curl and enter:

curl ifconfig.me

That command asks an external service to return the public IP used by your current connection. Note that if your device uses both IPv4 and IPv6, different connection paths can return different addresses.

The command line is handy for quickly confirming your egress address; an online tool is better for the details.

3. IP detection results: four things worth reading closely

Once the lookup finishes, don't fixate on location alone. The following are worth understanding too.

1. IP location and ASN

Say a lookup shows the IP is in Shanghai and the ASN belongs to a telecom carrier. That gives you a rough idea of where the connection comes from.

If the city doesn't match where you actually are, it doesn't automatically mean something is wrong. Carrier address allocation, slow database updates, and the location of the network egress can all skew the result.

2. DNS leak test

DNS is what turns domain names into IP addresses. A DNS check helps you see which servers are actually handling your resolution requests.

For example, your public IP shows Shanghai while the DNS check returns servers in Singapore. That alone doesn't prove a leak — public DNS services and network architecture can easily place the two in different cities.

To judge whether something is off, focus on whether the detected DNS servers match what you'd expect for your network, rather than simply comparing city names.

3. WebRTC test

WebRTC is the browser technology behind real-time audio and video. In some network setups, it can let a web page pick up additional network address information.

When reading the results, distinguish between private IPs, public IPs, and the mDNS addresses the browser generates. Seeing an internal address does not mean your real public IP has been exposed.

If the test page shows a public address you didn't expect, dig into your browser and network settings.

4. Browser language and time zone

Browser language, system time zone, and screen parameters can also influence what a site serves you.

For instance, your IP location shows the United States while your browser's preferred language is Simplified Chinese. That isn't necessarily a problem — people can use whichever language they're comfortable with, wherever they are.

So read the results against how you actually use the device. There's no need to force every parameter to line up.

4. Why doesn't IP location match your actual location?

Tip: if the IP location doesn't match where you are, check the ASN, ISP, and IP block first, then compare geolocation results across sources. City-level location is a reference point only — it shouldn't be the sole basis for judging where a device actually is.

5. IP address lookup: common questions

Q: Can an IP address reveal a specific home address?

Not through ordinary public lookups. IP geolocation isn't reliable at the street-address level.

Q: Will my IP definitely change when I switch networks?

Not necessarily. Public addresses may be assigned dynamically, or they may stay the same for a long time, depending on how your provider allocates them.

Q: Is online IP detection safe?

Legitimate lookup pages generally don't ask for account credentials. That said, any website can still see your IP, browser information, and whatever data its scripts can read. Stick to services you trust and check their privacy policy.

Q: How often should I run an IP check?

After changing networks, devices, or browsers. It's also worth rechecking when a site shows the wrong region, DNS resolution breaks, or you run into connection problems.

Final thoughts

An IP address lookup tells you where your public IP is located, and also gives you the ISP, ASN, and address block. Paired with DNS, WebRTC, and browser environment checks, it gives you a fuller picture of your current connection.

If you only want to confirm your public IP, a basic lookup is enough. If you're troubleshooting a network configuration issue, use ToDetect's online IP detection tool and work through the results one at a time.