Network tools
Free online network tools: IPv4 and IPv6 subnet calculators, VLSM splitter, CIDR to range and range to CIDR, wildcard masks, DNS lookup, MAC vendor lookup, port list and download time calculator.
IPv4IPv4 Subnet CalculatorNetwork, broadcast, host range and mask for any IP/CIDR.VLSMSubnet Splitter (VLSM)Divide a network into equal or different-sized subnets.IPv6IPv6 Subnet CalculatorExpand, compress and subnet IPv6 addresses and prefixes.4→6IPv4 to IPv6 ConverterConvert IPv4 to IPv4-mapped, 6to4 and NAT64 IPv6 forms.0xNumber Base ConverterConvert between binary, octal, decimal, hex and any base.CIDRCIDR to IP RangeFirst and last IP, size and mask of any CIDR block.→/IP Range to CIDRConvert ranges to CIDR and merge (summarise) CIDR lists.WCWildcard Mask CalculatorSubnet mask to wildcard mask, with Cisco ACL and OSPF examples.MACMAC Address LookupFind the vendor of a MAC address from the IEEE registry.MAC+MAC Address GeneratorRandom MAC addresses for VMs and tests, plus format converter.DNSDNS LookupCheck A, AAAA, MX, TXT, NS, SOA, CAA and other DNS records.:443Port Number LookupSearchable list of common TCP and UDP ports and services.MB/sDownload Time CalculatorHow long a file takes at a given speed, and the speed you need.