Nmap Command Builder
MAG212 CYBER · Tools
Nmap command builder: scan smarter, legally.
Choose a target and options and get the exact Nmap command, with every flag explained. Run it on networks you own or are authorised to test.
Build a command
Only scan what you’re allowed to. Scanning networks you don’t own or have written permission to test can be illegal and breach your ISP’s or cloud provider’s terms. For practice, Nmap’s authors provide
scanme.nmap.org — light scans only.Presets:
Target
IP, hostname, CIDR (10.0.0.0/24) or range (10.0.0.1-50). Separate several with spaces.
Scan type
Ports
Detection
Scripts (NSE)
Speed & options
Save results
Creates .nmap (readable), .xml (for tools and reports) and .gnmap (grep-friendly).
What each part does
Reading the results: port states
| State | Meaning | What to do |
|---|---|---|
| open | A service is accepting connections. | Confirm it should be exposed, patched and access-controlled. |
| closed | Host reachable, nothing listening on the port. | Fine — but a firewall could drop it instead. |
| filtered | No reply or an ICMP unreachable — a firewall is blocking probes. | Expected behind firewalls; scan from inside to see more. |
| unfiltered | Reachable, but open/closed unknown (ACK scan only). | Use a SYN or connect scan to decide. |
| open|filtered | No response — common for UDP. | Add -sV to send service-specific probes. |
| closed|filtered | Can’t tell closed from filtered (idle scan). | Rare; retry with another scan type. |
Found Telnet, SNMP or the HTTP admin interface open on a Cisco device? Paste its config into the Cisco config hardening checker.
Scan legally and safely
- Get written permission that names the targets, dates and allowed techniques before scanning anything you don’t own.
- Cloud providers (AWS, Azure, Google Cloud) allow scanning your own resources but publish rules — read them first.
- Start gently (
-T3or-T2, no intrusive scripts) on production networks; old printers, PLCs and medical devices can crash. - Tell your SOC or MSSP before scanning, so your scan isn’t treated as an attack.
- Install Nmap from the official site nmap.org/download. The reference guide at nmap.org/book/man.html documents every option.
Need an authorised vulnerability assessment of your network? MAG212 CYBER can help.
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