Free subnet & CIDR calculator
Drop in any IPv4 address and CIDR prefix. SightPlanr instantly shows the network, broadcast, mask, wildcard, host range and total usable addresses — perfect for planning camera VLANs and IT installs.
- Network
- 192.168.1.0/24
- Broadcast
- 192.168.1.255
- Subnet mask
- 255.255.255.0
- Wildcard
- 0.0.0.255
- First host
- 192.168.1.1
- Last host
- 192.168.1.254
- Usable hosts
- 254
What is CIDR notation?
Classless Inter-Domain Routing (CIDR) collapses an IP address and subnet mask into one compact form like 192.168.1.0/24. The number after the slash is how many bits belong to the network — the rest are available for hosts.
Picking a subnet for cameras
A typical 30-camera install fits comfortably inside a /27 (30 usable hosts) or /26 (62 usable hosts). Reserve room for NVRs, switches, APs and a few admin laptops before sizing.
Want help laying out the network?
Plan the cameras, switches and cable runs visually inside SightPlanr — then come back here to size the VLAN.
Ready to plan your install?
Open SightPlanr and design it in minutes — free, no credit card.