Free tools
Network tools
IP addressing, subnets, MAC addresses, ports and bandwidth.
IPv4 Subnet Calculator
Network, broadcast, usable host range, wildcard mask and binary view for any IPv4 address and CIDR prefix.
Open tool NetworkIPv6 Subnet Calculator
Prefix range, number of addresses and /64 networks, and a list of subnets when you split a delegation.
Open tool NetworkIPv6 Address Converter
Expand or compress any IPv6 address and see it as binary, decimal, hex groups and an ip6.arpa reverse DNS name – or turn a decimal number back into IPv6.
Open tool NetworkIPv6 Address Validator
Check whether an IPv6 address is valid and find out what kind it is – global unicast, link-local, unique local, multicast, documentation, IPv4-mapped and more.
Open tool NetworkIPv6 Cheat Sheet
IPv6 address types, special prefixes and prefix sizes on one page – a quick reference for planning and troubleshooting.
Open tool NetworkMAC Address Converter
Reformat a MAC address for Windows, Linux or Cisco, check its unicast/multicast and local/global bits, and derive the EUI-64 IPv6 link-local address.
Open tool NetworkIPv4 Address Converter
Convert an IPv4 address to decimal, hex, binary, octal and its IPv4-mapped IPv6 form – and back.
Open tool NetworkBandwidth & Transfer Time Calculator
How long will a backup, upload or migration take? Enter the size and link speed – with a realistic overhead allowance.
Open tool NetworkTCP/UDP Port Lookup
Search the well-known ports used by mail, web, remote access, databases, Windows domains and VoIP – with protocol and firewall notes.
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