Free Network Tools for IT Professionals

Port Lookup

Enter any port number between 0 and 65535 to find its service name, protocol, and description. Ports used by both TCP and UDP are shown as separate rows.

Lookup Result
Enter a port number above and click Search

Subnet Calculator

Enter an IPv4 address and subnet mask to calculate the network address, broadcast, host range, and more. The mask field accepts dotted decimal (255.255.255.0), CIDR prefix (/24), or a bare number (24).

Subnet Details
Enter an IP address and subnet mask above

CIDR Converter

Convert in either direction: enter a CIDR prefix (/24 or 24) to get the subnet mask, or enter a subnet mask (255.255.255.0) to get the CIDR prefix. A reference table of nearby prefixes is shown with each result.

Conversion Result
Enter a CIDR prefix or subnet mask above

IP Info

Enter any public IPv4 or IPv6 address to retrieve geolocation, ASN, hostname, and network details. Leave the field blank and click Lookup to check your own public IP address.

Enter an IP address or click Lookup to check your own

DNS Lookup

Enter a domain name and select a record type using the buttons below, then click Lookup. You can switch record types and run a new query at any time without re-entering the domain. Powered by Cloudflare's public DNS over HTTPS resolver.

DNS Records
Enter a domain name and select a record type