Free tools for ISPs

Calculators and lookups for planning and running a network. All free, with no sign-up.

Your connection

Speed testDownload, upload, ping and jitter, measured against the nearest Cloudflare edge.What is my IPYour public IP address, the network and ASN behind it, and your approximate city.DNS lookupLive A, AAAA, MX, TXT, NS, CNAME and SOA records for any domain.

IP addressing

Subnet calculatorNetwork, broadcast and host range for any IPv4 block, then split it into equal subnets.IPv6 subnet calculatorExpand an IPv6 prefix, count its /64s and split it into customer prefixes.CIDR calculatorTurn an IPv4 address range into the fewest CIDR blocks, or merge a list of blocks.CGNAT calculatorSubscribers per public IPv4 address, port block sizes and the pool you need.MAC address lookupThe vendor behind any MAC address, and whether the device randomised it.

Wireless and fiber

Link budget calculatorPath loss, EIRP, expected RSSI and fade margin for a point-to-point link.dBm to watt converterConvert RF power between dBm, milliwatts and watts, and dB gain to a ratio.GPON splitter calculatorFiber, splitter and connector loss against a PON optical budget, with a pass or fail.

Capacity and business

Bandwidth calculatorThe upstream an ISP needs from subscribers, package speed and contention ratio.Data and bandwidth converterConvert Mbps, Gbps, MB and GB, and work out how long a download takes.SLA uptime calculatorTurn an uptime percentage into the downtime it allows per day, week, month and year.UPS runtime calculatorHow long a battery bank keeps your equipment running at a given load.Tower revenue calculatorA tower's costs, revenue and the month it breaks even.