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More Developer Tools

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

Subnet Calculator

Calculate IPv4 subnet details from CIDR notation or a subnet mask. Get network, broadcast, and host ranges instantly.

CIDR notation

IP address

Prefix length

Common prefixes

Enter CIDR like 10.0.0.0/8 or adjust the IP and prefix controls separately.

Network address

192.168.1.0

CIDR block

192.168.1.0/24

Subnet mask

255.255.255.0

Wildcard mask

0.0.0.255

Broadcast address

192.168.1.255

IP address

192.168.1.10

First usable host

192.168.1.1

Last usable host

192.168.1.254

Usable hosts

254

Total addresses

256

IP class

C

IP type

Private (RFC 1918)

Binary IP

11000000.10101000.00000001.00001010

Binary mask

11111111.11111111.11111111.00000000