Network Tools
Calculate IPv4 subnets, CIDR blocks and IP ranges, format MAC addresses and look up ports.
IPv4 Subnet Calculator
Get the network, broadcast, host range, subnet and wildcard mask for any IPv4 address and prefix.
Open toolCIDR Calculator
Convert a CIDR prefix to a subnet mask, count addresses and split a network into smaller blocks.
Open toolIP Range to CIDR Calculator
Count the addresses between two IPv4 addresses and turn the range into the smallest CIDR list.
Open toolIP to Binary Converter
Convert IPv4 addresses to dotted binary and back, with hex and 32-bit integer forms.
Open toolMAC Address Formatter
Bulk-convert MAC addresses between colon, hyphen, Cisco dot and no-separator formats.
Open toolPort Number Lookup
Look up common TCP and UDP port numbers by number or service name, e.g. 22 SSH, 443 HTTPS.
Open toolCalculators for network admins and students
The subnet calculator instantly returns the network address, broadcast address, usable host range and wildcard mask for any IP and prefix. The CIDR calculator helps you split a block into smaller subnets.
Convert and look up
Convert IP addresses to binary to visualise subnetting, reformat MAC addresses for different devices and look up the port numbers of services such as SSH, HTTPS and RDP.
Exam practice
The clearly laid out results make a handy checker for anyone preparing for CCNA and other networking exams.