Leo's Lab
DevOps Tool Client-Side Only IPv4 Only

IP/CIDR Calculator

Calculate subnet information, validate IP addresses, and check CIDR range membership.

Network Input

Enter IP with optional CIDR notation (e.g., 10.0.0.0/8, 192.168.1.100/24)

Enter subnet mask to convert to CIDR

Check IP in Range

IP Address Validator

Common Subnet Reference

CIDR Subnet Mask Wildcard Hosts Usable
/8 255.0.0.0 0.255.255.255 16,777,216 16,777,214
/16 255.255.0.0 0.0.255.255 65,536 65,534
/24 255.255.255.0 0.0.0.255 256 254
/25 255.255.255.128 0.0.0.127 128 126
/26 255.255.255.192 0.0.0.63 64 62
/27 255.255.255.224 0.0.0.31 32 30
/28 255.255.255.240 0.0.0.15 16 14
/29 255.255.255.248 0.0.0.7 8 6
/30 255.255.255.252 0.0.0.3 4 2
/31 255.255.255.254 0.0.0.1 2 2*
/32 255.255.255.255 0.0.0.0 1 1

* /31 networks (RFC 3021) use both addresses for point-to-point links

Privacy Guarantee

  • All calculations happen locally in your browser
  • No IP addresses or network data is sent to any server
  • No network requests are made during calculation
  • IPv6 is not currently supported (IPv4 only)