> For the complete documentation index, see [llms.txt](https://docs.ipcheck.ing/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.ipcheck.ing/knowledge-base/lookup-privacy/dns-resolver.md).
# DNS Resolver
## What it does
Every time you open a website, your device asks a DNS resolver to turn the domain name into an IP address. Different resolvers can give different answers.
The **DNS Resolution** tool asks a list of well-known public resolvers the same question at the same time, then shows every answer side by side. You do not need to change any setting on your device. The lookups happen from the IPCheck.ing server, not from your computer.
This is the fastest way to see whether the answer your network gives you matches what the rest of the world sees.
## How to run it
{% stepper %}
{% step %}
### Open the tool
Go to **Advanced Tools** and click the **DNS Resolution** card. It opens in a panel. You can also open it as its own page at `/tools/dnsresolver`.
{% endstep %}
{% step %}
### Pick a record type
Under **Record**, choose one of `A`, `AAAA`, `CNAME`, `MX`, `NS`, `TXT`. `A` is selected by default and is the right choice for "which IP does this website use?".
{% endstep %}
{% step %}
### Enter a domain
Type a domain name or paste a full URL into the box. A URL works fine, because the tool takes the host name out of it. Press Enter, or click the play button.
{% endstep %}
{% endstepper %}
## Reading your results
Results appear in a two-column table: **DNS Provider** and **Resolution Result**.
Each provider name carries a tag:
| Tag | Meaning |
| ---------- | ---------------------------------------------------------------------- |
| `(DNS)` | Queried over plain DNS, the traditional unencrypted protocol. |
| `(DoH 🔒)` | Queried over DNS-over-HTTPS, an encrypted version of the same request. |
The providers queried over plain DNS are Google, Cloudflare, OpenDNS, Quad9, ControlD, AdGuard, AliDNS, DNSPod, 114DNS and DNS4EU. Google, Cloudflare, AdGuard and AliDNS are also queried over DoH, so you may see the same name twice with different tags.
`N/A` means that provider returned nothing. Either no record of that type exists, or the provider was unreachable from the server, or the request timed out. A single `N/A` is not a problem on its own.
### Why answers can differ, and why that is often normal
Different answers are common and usually harmless:
* **CDNs.** Large sites are served from many data centres. A resolver in Europe and a resolver in Asia get pointed at different edge servers.
* **Geo-DNS.** Some services answer with a different IP depending on where the question came from.
* **Load balancing.** A domain can have several IPs and hand them out in rotation, so two lookups a second apart can differ.
* **Caching.** A resolver may still be serving an older answer until its cache expires.
See [How DNS Works](/knowledge-base/concepts/how-dns-works.md) for the background.
### When a difference is suspicious
{% hint style="warning" %}
Some networks return deliberately wrong answers for certain domains. The tool says so in its own note: several of the built-in providers are based in China, and their answers for some domains may be polluted. Read the results with that in mind.
{% endhint %}
Patterns worth a second look:
* Most providers agree on one set of IPs, and one or two return something completely different.
* A provider returns a private or reserved address (something starting with `10.`, `192.168.`, or `127.`) for a public website.
* A provider returns an address that belongs to an unrelated network or country.
If you see one of these patterns, check what your own device is doing. It may be getting the same wrong answer.
Which record type should I choose?
* **A** — the IPv4 address of a website. Start here.
* **AAAA** — the IPv6 address of a website.
* **CNAME** — an alias pointing to another name. Common for sites behind a CDN.
* **MX** — the mail servers that receive email for the domain.
* **NS** — the authoritative name servers for the domain.
* **TXT** — free-form text records, used for domain verification and email rules such as SPF.
## What to do next
* Suspect your own resolver is the problem? Work through [Is My DNS Hijacked or Polluted?](/knowledge-base/diagnose/is-my-dns-hijacked.md).
* Want to know which resolvers your device actually uses? Run the [DNS Leak Test](/knowledge-base/connection-tools/dns-leak-test.md).
* A site will not open at all? Start with [Can't Open a Website?](/knowledge-base/diagnose/cant-open-a-website.md).
* Curious who owns an IP that came back? Look it up with [Whois Search](/knowledge-base/lookup-privacy/whois-search.md).
---
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