# masscan > Network scanner for scanning as fast as possible. > Best run with elevated privileges. Nmap compatibility run `masscan --nmap` to find out more. > More information: . - Scan an IP or network subnet for [p]ort 80: `masscan {{ip_address|network_prefix}} --ports {{80}}` - Scan a class B subnet for the top 100 ports at 100,000 packets per second: `masscan {{10.0.0.0/16}} --top-ports {{100}} --rate {{100000}}` - Scan a class B subnet avoiding ranges from a specific exclude file: `masscan {{10.0.0.0/16}} --top-ports {{100}} --excludefile {{path/to/file}}` - Scan the Internet for web servers running on port 80 and 443: `masscan {{0.0.0.0/0}} --ports {{80,443}} --rate {{10000000}}` - Scan the Internet for DNS servers running on UDP port 53: `masscan {{0.0.0.0/0}} --ports {{U:53}} --rate {{10000000}}` - Scan the Internet for a specific port range and export to a file: `masscan {{0.0.0.0/0}} --ports {{0-65535}} --output-format {{binary|grepable|json|list|xml}} --output-filename {{path/to/file}}` - Read binary scan results from a file and output to `stdout`: `masscan --readscan {{path/to/file}}`