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More Developer Tools

Subnet CalculatorCalculate IPv4 subnet details from CIDR notation or a subnet mask. Get network, broadcast, and host ranges instantly.
IP Address LookupLook up geolocation, ISP, ASN, reverse DNS, and IP format details for any public IPv4 or IPv6 address.
Reverse DNS LookupLook up PTR reverse DNS records for a public IP address. Resolve hostnames and verify forward DNS (FCrDNS) alignment.
DNS LookupQuery public DNS records for any domain — A, AAAA, MX, TXT, NS, CNAME, SOA, SRV, CAA, and PTR.
Port ScannerScan common TCP ports on a public host — check which services are reachable from the server.
Traceroute ToolTrace the network path to a hostname or IP. Shows each hop, round-trip times, and whether the route completed.

CIDR Calculator

Analyze CIDR blocks, convert prefix lengths to subnet masks, split networks, and check whether an IP belongs to a range.

CIDR block

CIDR block

10.20.0.0/22

Subnet mask

255.255.252.0

Wildcard mask

0.0.3.255

Network bits

22

Host bits

10

Total addresses

1,024

Usable hosts

1,022

First address

10.20.0.0

Last address

10.20.3.255

First usable host

10.20.0.1

Last usable host

10.20.3.254

Binary network

00001010.00010100.00000000.00000000