# nslookup — DNS Queries from the Command Line

> Practical guide to nslookup – resolve domain names, check mail records and perform reverse DNS lookups on Windows, macOS and Linux, no extra installation needed.

Source: https://www.jpkc.com/db/en/cheatsheets/networking/nslookup/

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nslookup is a cross-platform DNS query tool that ships with Windows, macOS and Linux – no extra installation needed. A single command resolves domain names, checks mail records or traces nameserver delegations. On Unix systems `dig` offers more power and better scriptability; nslookup wins on availability, especially in Windows environments or when you need a quick ad-hoc check on an unfamiliar server.
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## Non-Interactive Queries

`nslookup DOMAIN` — Look up the A record of a domain using the default DNS server.

```bash
nslookup example.com
```

`nslookup DOMAIN SERVER` — Look up a domain using a specific DNS server.

```bash
nslookup example.com 8.8.8.8
```

`nslookup IP` — Reverse DNS lookup — find the hostname for an IP.

```bash
nslookup 8.8.8.8
```

`nslookup -type=TYPE DOMAIN` — Query a specific record type.

```bash
nslookup -type=MX example.com
```

`nslookup -query=TYPE DOMAIN` — Alternative syntax for record type queries.

```bash
nslookup -query=TXT example.com
```

## Record Type Queries

`nslookup -type=A DOMAIN` — Query IPv4 address records.

```bash
nslookup -type=A example.com
```

`nslookup -type=AAAA DOMAIN` — Query IPv6 address records.

```bash
nslookup -type=AAAA example.com
```

`nslookup -type=MX DOMAIN` — Query mail exchange records.

```bash
nslookup -type=MX example.com
```

`nslookup -type=NS DOMAIN` — Query nameserver records.

```bash
nslookup -type=NS example.com
```

`nslookup -type=TXT DOMAIN` — Query text records (SPF, DKIM, DMARC).

```bash
nslookup -type=TXT example.com
```

`nslookup -type=SOA DOMAIN` — Query Start of Authority record.

```bash
nslookup -type=SOA example.com
```

`nslookup -type=CNAME DOMAIN` — Query canonical name (alias) records.

```bash
nslookup -type=CNAME www.example.com
```

`nslookup -type=SRV SERVICE DOMAIN` — Query service records.

```bash
nslookup -type=SRV _sip._tcp.example.com
```

`nslookup -type=PTR IP.in-addr.arpa` — Explicit PTR record lookup for reverse DNS — write the octets in reverse order.

```bash
nslookup -type=PTR 8.8.8.8.in-addr.arpa
```

`nslookup -type=ANY DOMAIN` — Query all record types. Many servers restrict this.

```bash
nslookup -type=ANY example.com
```

## Options

`nslookup -debug DOMAIN` — Show detailed query and response information.

```bash
nslookup -debug example.com
```

`nslookup -timeout=SECONDS DOMAIN` — Set the query timeout.

```bash
nslookup -timeout=10 example.com
```

`nslookup -retry=N DOMAIN` — Set the number of retries.

```bash
nslookup -retry=3 example.com
```

`nslookup -port=PORT DOMAIN SERVER` — Use a non-standard DNS port.

```bash
nslookup -port=5353 example.com 127.0.0.1
```

## Interactive Mode

`nslookup` — Enter interactive mode. Type domain names to look them up.

```bash
nslookup
> example.com
> google.com
```

`> server SERVER` — In interactive mode: switch to a different DNS server.

```bash
> server 8.8.8.8
```

`> set type=TYPE` — In interactive mode: set the default query type.

```bash
> set type=MX
```

`> set debug` — In interactive mode: enable debug output.

```bash
> set debug
```

`> set nodebug` — In interactive mode: disable debug output.

```bash
> set nodebug
```

`> set all` — In interactive mode: show current settings.

```bash
> set all
```

`> exit` — In interactive mode: exit nslookup.

```bash
> exit
```

## Common Patterns

`nslookup -type=TXT _dmarc.DOMAIN` — Check DMARC policy for a domain.

```bash
nslookup -type=TXT _dmarc.example.com
```

`nslookup -type=TXT DOMAIN | grep 'v=spf'` — Check SPF record for a domain.

```bash
nslookup -type=TXT example.com | grep 'v=spf'
```

`nslookup DOMAIN 8.8.8.8` — Quick check using Google's public DNS.

```bash
nslookup example.com 8.8.8.8
```

`nslookup DOMAIN 1.1.1.1` — Quick check using Cloudflare's public DNS.

```bash
nslookup example.com 1.1.1.1
```

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## Conclusion

nslookup handles DNS queries quickly on any operating system, with no setup required. For regular DNS debugging on Unix, `dig` or `host` are more capable; nslookup remains the universal fallback that works everywhere. A quick MX check or reverse lookup is done in seconds.

## Further Reading

- [nslookup – Wikipedia](https://en.wikipedia.org/wiki/Nslookup) – background and history
- [nslookup – Microsoft Learn](https://learn.microsoft.com/en-us/windows-server/administration/windows-commands/nslookup) – Windows reference
- [dig – alternative DNS query tool](https://linux.die.net/man/1/dig) – more powerful on Unix systems
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## Related Commands

- [dig](https://www.jpkc.com/db/en/cheatsheets/networking/dig/) – perform detailed DNS record queries and diagnostics
- [host](https://www.jpkc.com/db/en/cheatsheets/networking/host/) – compact DNS lookup for quick checks
- [ping](https://www.jpkc.com/db/en/cheatsheets/networking/ping/) – test host reachability and measure response times